‘4 LEEEUEBY Miefiigmi mate Umivemity —_—-— OVERDUE FINES: 25¢ per day per 1w RETURNING LIBRARY MATERIALS: Place in book return to name din-9e from circuution records THE RELATIONSHIPS AMONG FLOWERING TIME, POLLINATORS, AND SEED SET OF INDIVIDUALS OF FOUR SPECIES OF GOLDENROD (SOLIDAGO: COMPOSITAE) By Ronald Scott Gross A DISSERTATION Submitted to Michigan State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY W. K. Kellogg Biological Station and Department of Botany and Plant Pathology 1981 '5’ " 1) f. m: ABSTRACT THE RELATIONSHIPS AMONG FLOWERING TIME, POLLINATORS, AND SEED SET OF INDIVIDUALS OF FOUR SPECIES OF GOLDENROD (SOLIDAGO: COMPOSITAE) BY Ronald Scott Cross The relationship between flowering phenology and seed set (percentage of filled seeds and total production) was investigated for individuals of four species of goldenrod, Solidago canadensis, S, graminifolia, S, nemoralis, and S, Juncea. The seed set of individuals which flowered at different times was related to the timing and frequency of visits by pollinators and flower predators. Experimental crosses were performed to determine if seed set was limited by the amount of pollen reaching stigmas (i.e. by pollinators or flower predators) or by physiological factors intrinsic to individual plants which flowered at different times. Within the population of each species of goldenrod, there were great differences among the flowering phenologies of individual clones. For S, canadensis, there was a highly significant positive correlation between the relative phenology ranks (early- to late-flowering) of clones flowering in 1979 and 1980. All four species of Solidago exhibited significant differences in the percentage of filled seeds among clones which flowered at different times. Early-flowering clones had lower percentages of filled seeds than late-flowering clones in S, canadensis, S, gaminifolia, and _S_. nemoralis. In contrast, _S_. luncea showed a decrease in the percentage of filled seeds from.early- to Ronald S. Gross late-flowering clones or ramets. The same results were obtained in terms of total seed production for all four species. (Apis mellifera, the introduced honeybee, was the major pollinator of _S_. canadensis, _S_. graminifolia, and S_. nemoralis. Solidago luncea was visited mainly by small, native bees and beetles. Seasonal changes in the abundance of honeybees on different goldenrods were correlated with differences in seed set for clones with different flowering times. The major factor influencing the relative densities of honeybees on goldenrods seemed to be overlap among the flowering periods of goldenrods and several introduced plant species. Epicauta pennsylvanica (blister beetle) were flower predators which caused reductions in the seed set of Solidago clones. However, only in S, graminifolia did beetles clearly have a differential effect on the seed set of clones flowering at different times. Experimental crosses suggested that seed set was not always limited by pollinators or flower predators; physiological or genetic factors were also important determinants of seed set. In.§, canadensis, the percentage of filled seeds was significantly lower than the potential maximum seed set (determined by experimental pollinations) of clones flowering at different times. Pollinator limitation was estimated to account for 83-942 of the difference in seed set between untreated clones and experimental crosses. Clones which flowered at different times had different maximum potential seed sets. Late-flowering S, canadensis clones had greater physiological potential for seed set relative to early-flowering clones. In S, graminifolia, the seed set of early-flowering clones was significantly lower than the maximum potential seed set. A low Ronald 8. Gross frequency of honeybee visits was estimated to account for 701 of the reduction of seed set from the potential maximum; the remainder of the reduction was attributed to predation by blister beetles. The lack of honeybees early in the flowering season apparently resulted from competition for pollinators with co-occurring plant species introduced from.Eur0pe. Late-flowering clones of S, graminifolia were near their maximum potential seed set. Seed production of S, luncea ramets was close to the potential maximum at all times during the flowering season, and it was not possible to determine which factors were most important in producing the differences in seed set for ramets that flowered at different times. To Ellen - for auld lang syne ii ACKNOWLEDGEMENTS I would like to offer sincere thanks to my advisor, Dr. Patricia Werner, for her continual support, advice and encouragement throughout my graduate studies. I am very grateful to Dr. Werner for her extensive comments on an earlier draft of this dissertation. I have a debt of gratitude to all my committee members, Drs. Patricia Werner, Susan Kephart, Peter Murphy, Stephen Stephenson, and Donald Hall, for their unwavering support and patient guidance and for critically reviewing an earlier draft of this dissertation. The ideas and questions which laid the foundation of this investigation would not have developed without the benefit of lively discussion and stimulating interaction with my fellow graduate students in the Ecology group at Michigan State University. Special thanks go to Ray Gross, Judy Soule, Beth Hutchinson, Ed Turanchik, and Ann Hedrick for their critical advice and for their words of encouragement during times of personal frustration. I would also like to offer personal thanks to Drs. Deborah Goldberg and Claudia Jolls for their invaluable advice and support throughout much of this investigation. This study would not have been possible without the dedicated and competent field assistance provided by Angel Bair. Throughout the course of these investigations many people provided valuable technical and field assistance including Jan Grace, Kathy Weist, Alice Winn, Jeff waldeck, and Penny Meints. Thanks are also extended to Charlotte iii Seeley and Arthur Weist for their assistance. John Gorentz and Steve Weiss provided valuable assistance on data management and analysis on the KBS computer system. Very personal and heartfelt thanks are extended to my parents, grandmother, and sister for their continual support through hard times and for their sincere delight when clouds revealed their silver linings. I would like to thank all my friends, new and old, who have helped me maintain the mix of comforting friendship and episodic chaos which makes life interesting. Finally, I do not have enough kind words for Ellen Dreyfuss, whose friendship, guidance and encouragement may eventually place everything in its proper perspective. Financial support for this work was provided by NSF grants DEB 77-14811 and DEB 79-23945 to Patricia Werner. iv TABLE OF CONTENTS LIST OF TABLES 0.00....COO...00.0.0.0...OOOOOOOOOOOOOOOOOOOOOOO LIST OF FIGURES OOOOOOODOOOOI.OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO CHAPTER I: INTRODUCTION AND STUDY SYSTEMoooooooooooooooooooooo IntrOdUCtion I...O0.0.0.0....00......OCOOOOOOOOOOOOOOOOOOO StUdy SYStem ooooooases-o0.000000000000000000000000000000o CHAPTER 2: METHODS 0.0.0.0000...O...OOOOOOOOOOOOOOOOOOOOOOOOO. Marking BHd Monitoring PhfiflOlogy Of SOlidago 0000000000000 888d COlleCtion a0000000000000000000000000000000000000000o SCEd Set ooone...0000000000000oooso.00000000000000.0000... Percentage 0f Viable Seeds oso...00000000000000.0000. Tatal PrOdUCtion 00000000000000000.000000000000000... Flowering Phenology of Other Species ..................... InseCt Sampling 00000000000000000000000000.000000000000000 cr0881ng StUdies o00000000000000.0000.00000000000000.0000. compatibility Experiments 00000000000000.000.000.000. Pollination Versus PhYBiOlogy ooooooooooosooooooooooo CHAPTER 3: RESULTS O00......O0....0..OOOOOOOOOOOOOOOOOOOOOOOOO Compatibility Experiments oooooooooooo00000000000000.0000o Flowering PhCflOlogy ooooooooooooooaoooooeo0000000000000... Seed Set as a Function of Flowering Phenology ............ CODBtrUCtion 0f PhCflOlogy Groups 00000000000000.0000. Relationships of Phenology Groups to Seed Set ....... Patterns 0f InseCt Abundance 0.000.000.000000000000000000. The Relationship Between Seed Production and Insect Abundance one.000000000000cocoons00000000000000.0000o The Relationship Between Goldenrods and the Plant Community 0000000so.so.so.so.00000000000000.0000...so Seed Predation sooso...soone...sooooooooooeooooooooooooooo Experimental Crosses oso.one.ooooooooooooooooooooooosooooo $011dqu canadensis 0000000000000.0000000000000000... ‘Szlidago staminifdlia 00000000000000.0000...000000000 Solidago luncea oso.oooooooooooooooooo0000000000000so ‘znAPTER 4: DISCUSSION OOOOOOOOOIOOOOOOOOOOOOOIOOOOOOOO00...... Factors Affecting Flowering Time Within Natural POPUlationsoooooooooso.oooooooooooooooooooooooooooooo Page vii viii 12 12 14 16 16 21 22 22 25 25 3O 33 33 33 42 42 43 58 71 84 88 89 95 96 105 105 TABLE OF CONTENTS (continued) Page Factors Limiting Seed Production in Goldenrods ........... 107 Implications for the Study of Competition for POllinators 0000000000000000000000000000000000000000. 124 Implications for the Evolution of Flowering Time and the SttUCture Of Plant communities 0.0000000000000000 134 CHAPTER 5: SMARY O0.0.0.0000...O0..0.00000000000000000000000 144 LITERATIJRE CITED 0.0.000...O00.00.0000...OOOOOOOOOOOOOOOO0.0... 147 APPENDIX A: Results of Experimental Crosses for Individual Clones or Ramets of Solidago canadensis, S, ‘graminifolia, and.§3 luncea oooooooooooooooooooooo 154 APPENDIX B: Data on Phenology, Seed Set, and Size of Individual Clones and Ramets of Solidago app. in 1980 o0000000000000000000000.0000...use... 158 APPENDIX C: Data on Flowering Phenology and Insect Visitors for Individual Clones and Ramets of Solidago app. on Several Census Dates in 1980 ............. 169 vi Table 10 11 LIST OF TABLES Morphological Features of Four Species of SOlidagO OOOOOOOOOOOOOOOOOOOOO...OOOOOOOOOOOOOOOOOOO. Methods for Determining Flowering Phenologies for the Common Bee-Visited Plants in the Vicinity of the StUdy Areas coo.oooooooooooooooooooooooooooooooso Methods and Dates for Insect Samples from Solidago app. OI0.000000000000000000000000000000000IOOOOO...O. Percentages of Filled Seeds from Compatibility Experiments 0000000000.0000000000000000...ooooooooooo Percentage of Filled Seeds per Clone or Ramet in the E, I, and L Phen0108y Groups 0.000000000000000... Percentage of Filled Seeds per Clone in the E, I, and L Phenology Groups of S, iuncea and S, nemoralis O0.0.0.000...0......OOOOOOOOODOOOOOOOOO0.0. Volume of Seeds per Inflorescence in E, I, and L PheUOIOgy Groups 000000000000000000000000000.0000.coo S, canadensis: Percentage of Filled Seeds in Experimental Crosses 000000000000000000000000.0000soo S, graminifolia: Percentage of Filled Seeds in Experimental Crosses 00000000.00000000000000.0000.coo S, canadensis: Percentage of Filled Seeds per Clone in Early, Intermediate, and Late Phenology Groups Using All Clones and Using Only Clones "hICh Were NOt Visited by Blister Beetles 00000000000 Reductions from Potential Maximum Seed Set Partitioned into Pollinator and Predator Limitation 00000000000.0000000000000000...ooooooooooo vii Page 23 24 34 44 55 57 9O 98 123 124a Figure 10 11 12 LIST OF FIGURES Frequency Distributions of Weights of Filled and Unfilled Seeds Of E: canad80818 0.0000000000000000... Total Numbers of Chauliognathus and Apis Counted During Visual Censuses Over the Course of One Day onlgf canaden818 O...0.0.0....OOOOOOOOOOOOOOOIOIOOOO. Total Numbers of Chauliognathus and Apis Counted During Visual Censuses Over the Course of One Day on‘éf gram1n1f01ia 0..OOOOOOOOOOOOOOOOOOOOOOOO0...... Flowering Phenology of Four Species of Solidago in 1980 OCOO...000......OOOOOOOOOOOOOOOOOOO0.0.0.0... Cumulative Frequencies of Clones or Ramets Largely Past Flowering for Four Species of Solidago in 1980 OOOOOOOCOOOOOOOOOOO00....OOOOOOOOOOOOOOOOCOOO... Cumulative Frequencies of S, graminifolia and S. canadensis Clones Largely Past Flowering in 1979 and 1980 .0.0.0.0....O...OOOOOOOOOOOOOOOOOOOO0.00...O Percentage of Filled Seeds Versus the Relative Phenology Ranks (1 - 23) of S, canadensis Clones in 1980 aas000000000000ooooooooooooooooooooooo Percentage of Filled Seeds Versus the Relative Phenology Ranks (1 - 19) of S, ggaminifolia Clones in 1980 o0000000000000000000000000.0000.oooooo Percentage of Filled Seeds Versus the Relative Phenology Ranks (1 - 31) of S, nemoralis Ramets in 1980 .0.00.0.0000...OOOOOOOOOOOOOOOOOOOI... Percentage of Filled Seeds Versus the Relative Phenology Ranks (1 - 38) of S, juncea ramets in 1980 O000......OOOOOOOOOOOOOOOOOOOOO00.000.000.00. Total Numbers of Major Insect Visitors Counted During Visual Censuses of S, graminifolia Clones in 1980 oso...oneso.one...00000000000000.0000. Total Numbers of Major Insect Visitors Counted During Sweep-Sample Censuses of S, graminifolia Clones in 1980 .0.0.0...O...0.00.0.0...OOOOOOOOOOOOOO viii Page 20 27 29 36 38 41 46 48 50 52 62 64 Figure Page 13 Total Numbers of Major Insect Visitors Counted During Visual Censuses of S, canadensis Clones in 1980 O0.0000000000000000000000000.000.00.00..0.COO 66 14 Total Numbers of Major Insect Visitors Collected During Sweep-Sample Censuses of S, canadensis Clones in 1980 oooooooeooooooooooooooooo0000000000000 68 15 Total Numbers of Major Insect Visitors Collected During Sweep Sample Censuses of S, nemoralis Ramets in 1980 OOOOOOOOOOOOOOOOOOOOOOIOOOOOOOOOOOO... 70 16 Percentage of Filled Seeds for S, canadensis Clones Assigned to Different Maximum Flowering Dates (MFD) in 1980 ooooooooooooooooooooooooooooooooo 75 17 Percentage of Filled Seeds for S, graminifolia Clones Assigned to Different Maximum Flowering Dates (MFD) in 1980 o0.0000000000000000000000000ooooo 77 18 Percentage of Filled Seeds for S, nemoralis Ramets Assigned to Different Maximum Flowering Dates (MFD) in 1980 00000000000000.0000...00000000000 79 19 Percentage of Filled Seeds for S, juncea Ramets Assigned to Different Maximum Flowering Dates (MFD) in 1980 O0......OOOOOOOOOOOOOOOOOOOOO0.0....000 81 20 Flowering Phenologies of Four Goldenrods and Six of the Common Bee-Visited Plant Species in the Vicinity Of the StUdy Sites 0.0000000000000000...oooo 87 21 Percentage of Filled Seeds from OPEN CROSSES, BAG CROSSES, and BAG CONTROLS from S, canadensis Clones in Different PhenOIOgy Groups oooooosooooooooo 92 22 Percentage of Filled Seeds from OPEN CROSSES and Untreated Clones of S, canadensis in Different PhEflOlogy Groups 00000000000000.00000000000000000oooo 94 23 Percentage of Filled Seeds from OPEN CROSSES, BAG CROSSES, and BAG CONTROLS from S, graminifolia Clones in Different PhenOIOgy Groups 0000000000000... 100 24 Percentage of Filled Seeds from OPEN CROSSES and Untreated Clones of S, gggminifolia in Different PhenOIOgy Groups o00000000000000ooooooooooo 102 25 Percentage of Filled Seeds from OPEN CROSSES, BAG CONTROLS, and Untreated Ramets of S, juncea in Different PhenOIOgy Groups ooooooooooooooooooooooo 104 ix Figure Page 26 Volume of Seeds per Inflorescence and Percentage of Filled Seeds per Clone for S, canadensis Clones in Different PhQDOlogy Groups 0000.........0.0 112 27 Relationship Between Percentage of Filled Seeds and Distance to Nearest Neighbor for _S_. canaden818 Clones .0........0.00....0..0.000.00...00. 115 28 Relationship Between Percentage of Filled Seeds and Density of Epicauta (Blister Beetles) for §,l£§am1n1folia Clones in 1980 00.00..........0..00.. 120 29 Relationship Between Percentage of Filled Seeds and Density of Epicauta (Blister Beetles) for E} canaden818 Clones in 1980 00.0.0.....0.000..000..0 122 30 Total Numbers of A213 Collected in Sweep-Sample Censuses of Solidago canadensis and Aster pilosus in MCKay Field, 1980 0000........0..0.....0..000.00.. 131 CHAPTER 1 INTRODUCTION Recently, there has been a great deal of interest in elucidating the ecological factors which influence the evolution of flowering time in co-occurring plant species. Because it has frequently been noted that co-occurring plant species which could utilize the same pollinators tend to flower at different times (e.g. Opler et a1. 1975), numerous authors have suggested that these plant species have undergone selection to reduce interspecific competition for pollinators by displacing their flowering periods (Robertson 1895; Mosquin 1971; Frankie et a1. 1974; Gentry 1974; Pojar 1974; Frankie 1975; Heinrich 1975, 1976; Heithaus et al. 1975; Stiles 1975, 1977; Reader 1975; Croat 1969; Feinsinger 1976; Carpenter 1976; Waser 1978; Anderson and Schelfhout 1980; Pleasants 1980). To demonstrate selection for flowering time in plant populations, it is necessary to document that individuals exhibit differential seed set as a function of their flowering time. It is therefore unfortunate that very few studies have investigated the relationships among flowering time, pollinator availability and seed set for individual plants in natural populations. Several studies have shown that flowers opened at different times during the flowering season of a population exhibit differential seed set (Barrett 1980; Carpenter 1976; Schemske 1977; Schemscke et a1. 1978; Maser 1978; woodell et a1. 1977; Zimmerman l980a,b; Melampy and Hayworth 1980). Most of these studies have used flowers which opened at.different times within marked plants or inflorescences (woodell et a1. 1977 made random collections of inflorescences). But, although these studies have shown differences in seed set per flower, they have not demonstrated differences in total seed production for individuals flowering at different times during the flowering season of the population. This stems largely from the fact that these studies did not (or because of extensive cloning, could not) explicitly relate the flowering phenology of individual plants to the flowering phenology of the population. A few studies have explicitly shown that plants with different flowering times had differential seed set (Primack 1980; Waser 1979; Augspurger 1978 cited in Augspurger 1980). In order to show that competition for pollinators causes differential reproduction in plants which flower at different times during their flowering season, it is necessary to demonstrate that pollination is limiting seed set. This requires data not only on the availability of pollinators, but also on potential physiological differences or environmental differences among plants flowering at different times. Physiological causes for changes in seed set could be ruled out by performing experimental crosses on clones flowering at different times throughout the flowering season. If seed set remains constant over the season in these crosses, then differences in seed set may be ascribed to the amount of effective pollen reaching the stigmas. Of the studies which record changes in seed set over the flowering season, only Barrett (1980) has performed experimental crosses to be compared with seed set in open-pollinated flowers at different times during the flowering season. He was able to convincingly demonstrate that seed set was pollinator-limited throughout the flowering season. Combinations of data on crossing success and rates of ovule abortion have been used to provide reasonable arguments for the relative importance of pollinators and environmental conditions as factors limiting seed production (Schemske 1977; Schemske et a1. 1978; Melampy and Hayworth 1980). However, potential temporal variation in self- fertility (Pinthus 1959) or pollen viability (Woodell et al. 1977) still argues for the need to perform experimental crosses. The results of the present study show that experimental crosses performed on plants flowering at different times during the flowering season can yield very different results, thereby demonstrating the necessity of performing experimental crosses throughout the flowering season. Many explanations have been offered to account for the differential seed set of flowers opened at different times. Waser (1978) provides very strong evidence for the importance of competition through interspecific pollen transfer (see Discussion) while Zimmerman (1980a), Barrett (1980), and Melampy and Hayworth (1980) provide more equivocal, but highly suggestive, evidence for the importance of competition for pollinators acting through differential pollinator attraction. It is clear that along with competition for pollinators, seed predation (Zimmerman 1980b), abiotic conditions (Schemske 1977; Schemske et al. 1978) and spatial density of plants and flowers (Augspurger 1980; Carpenter 1976) will also be important factors affecting seed set during the flowering season in natural populations and communities of plants. The experimental study reported here is an investigation of the population- and individual-level processes which affect seed set throughout the course of the flowering season for four co-occurring species of goldenrod (Solidago spp.). The relationship between seed set and flowering time of individual plants is documented and patterns of seed set are correlated with abundances of insect pollinators and flower predators. These results are compared with experimental crosses which suggest that changes in seed set over the flowering season are not simply a function of pollinator availability or behavior, but also a function of environmental and/or physiological constraints on seed set. These and other data which bear on the potential importance of competition for pollinators between goldenrods and the rest of the plant community will be discussed using goldenrods as a model system to point out the mechanisms by which competition for pollinators and selection for flowering time can occur in natural populations of other plant species. THE STUDY SYSTEM The genus Solidago (goldenrod, Compositae) contains approximately 100 species of perennial herbs, almost all of which are native to North America (Willis 1973). The four species involved in the study reported here, Solidago canadensis L., _S_. graminifolia (L.) Salisb., S. nemoralis Ait., and S, juncea Ait., are native species which are widely distributed east of the Rocky Mountains. These goldenrods are frequently found co-occurring in abandoned fields and grasslands and along roadsides throughout midwestern and northeastern North America. Where they co-occur, the four species tend to separate out over edaphic gradients. Solidago graminifolia and S, canadensis are most common on wet sites, while S, nemoralis and S, juncea are most common on dry sites (Werner and Platt 1976). All four species are very abundant in southwestern Michigan where they co-occur in fields of various ages at the Kellogg Biological Station (KBS) in Kalamazoo Co., Michigan. Some basic morphological features of the four species are summarized in Table 1. Additional information on the life history characteristics of these species is presented in Werner and Flatt (1976) and Werner (1979) (Solidago juncea was identified as S, missouriensis in the old-field data reported in these papers). A complete review of the biology of S, canadensis can be found in Werner et a1. (1980). The taxonomic status of S, canadensis is complex (see Werner et al. for a review) and most authors do not make clear what variants of S, canadensis were used in their studies. Unless otherwise specified, S. canadensis hereinafter refers to S, canadensis var. scabra (Muhl.) T. a G. (- S, altissima L.). A comparative study of S, canadensis var. scabra and S, canadensis var. canadensis will be presented in a separate paper. The taxonomic status of the other three goldenrods is relatively clear; all four species are easily distinguished within a single field. Nomenclature for all species follows Gleason and Cronquist (1963). With the exception of S, nemoralis, these goldenrods are rhizomatous and exhibit extensive clonal growth; clones up to 2.5m in diameter may be found in a 25-year-old abandoned field. However, Solidago Juncea is differentiated from S. canadensis and S. graminifolia in that a small percentage (approximately 32) of the ramets in a clone flower in any given year. Solidagg canadensis and S, graminifolia have a much larger percentage of ramets flowering in a given year (34-542 in S, canadensis; Bradbury 1981). Solidago canadensis and S, graminifolia form dense clumps of flowering ramets; S, juncea forms a more diffuse group of flowering ramets. .voswwoz sum: omuneo voaoao>ov w saw: ammo. voaawm mace mo unwaua hum co comma one magmas: Aoconomv comm .vo>oaou cannon gags ammo. .Amumv mozmaaaancav uHHoH .A .o flown mama N .Aouo—v uumHm we. nocuom.a0uu mama a sous wcauomoau oawaqm m o>m: mucmfie Auuwv umoe “Romano Acmwzv AMWZV motocmun m Eoum moan. hoe mamas a.m+~.em oom+o0s.q Ne CAIN mo enemas Hams. noauuua mafiouoauc .m common moms Acmwzv Amwzv auron nuoamu 30w “mocoao .I m.v+o.aa oo-+ooo.w we omsuwwv .owumH mEhOm u0>wmcouxm moons" .m common some Apmwzv Afiwwzv uosofiu muoamu mama “enemas I. w.~+¢.oe oo~e+¢om.o~ hm omcov .owumH oeuou uo>uocouxm oaaouuaaammu .m common comm AOMIzV Ammlzv ummoHu museum acme unmanao o.wHw.~e oooeHdoo.o~ ~o~ omcov .owuma «Show mo>wncouxm oumcovoaou am :8 H we 9... H my 2.3 inseam 9:88 .303...“ Am v unwaos uwamu use «comm muosoam .mcwwa mum woaam> HH< .owmvfiaom uo mouooom usom mo mouaumom HmonOHonauoz “u wanna All species of Solidago in the northeastern United States bloom in mid- to late-summer and fall (Gleason and Cronquist 1963). Solidago uncea, early goldenrod, begins flowering in late-July; it is followed by _S_. graminifolia in mid-August and _S_. canadensis and _S_. nemoralis in late-August to early-September. There is extensive overlap among the flowering periods of §, canadensis, g, nemoralis, and g, graminifolia. Almost the entire flowering period of E, juncea and the early portion of the flowering period of §, graminifolia overlap with the flowering periods of many plants introduced from Europe; the introduced plants are abundant in the summer flora. The latter portions of the flowering periods of g, canadensis and g, nemoralis overlap with the flowering periods of several 飣g£_species. All four goldenrods have two kinds of yellow flowers which are aggregated into heads (capitula). The more numerous ray flowers are pistillate, while the central disc flowers are hermaphroditic. The heads of §, canadensis, §3 nemoralis, and g, Juncea are aggregated into terminal, paniculiform (branched, elongate) inflorescences; g. graminifolia is distinguished by its corybiform (flat-topped) inflorescence. All four species of Solidago are self-incompatible and require pollinators to set seed (Mulligan and Findlay 1970, and below). Within a capitulum, the pistillate ray flowers mature first and are receptive to pollen for several days prior to the maturation of the disc flowers. The disc flowers are protandrous; before the stigmatic surface becomes receptive, the stigma pushes up through the five fused anthers carrying with it a load of pollen. Observations on flowers not exposed to insect visits suggest that heads (capitula) may be receptive to pollen for approximately 7-9 days. Similar results were obtained from.Observations on several fists: species (Jones 1978). The marked similarity with respect to the size, color, and general morphology of the flowers of the different goldenrods suggests that they are all capable of utilizing the same species of insect pollinators and that the same insects could be attracted by all four species of Solidago. All four goldenrods provide nectar rewards for foraging pollinators. Heinrich (1976a) reports means of 0.0024 and 0.024 mg sugar per flower for §3 canadensis and g, graminifolia, respectively. However, the data reported in Heinrich (1979a) suggest that these values may represent mean nectar rewards per capitulum. Heinrich (1979a) reported nectar rewards of 0.0024 mg sugar per flower and 0.0001 mg sugar per floret (actually a flower) for §3 canadensis. No measures of nectar production are available for §_. nemoralis and _§_. luncea. Although individual flowers provide very small quantities of nectar, a large clone of Solidago may have more than a million flowers. The dense aggregation of flowers and the ease with which individual flowers are handled by foragers makes Solidago spp. very attractive to foraging bees (Heinrich 1979a,b). All four species of Solidago are pollinated by insects. In the study areas at KBS, the major pollinators are the introduced honeybee (Apis mellifera L.), various small, native bees (especially Ceratina spp. and Halictus spp.), several wasps (mainly Polistes spp.), and isoldier beetles (Chauliognathus pennsylvanicus (DeGeer)). Although these insects all carry goldenrod pollen and exhibit foraging behavior which would transfer this pollen to goldenrod stigmas, the different :insects are not equally important pollinators of goldenrods in the study areas. Wasps generally do not carry large amounts of goldenrod pollen and they are not very abundant visitors to any of the four species of Solidago. Soldier beetles often carry many pollen grains of Solidago spp. and at times may be very abundant visitors to goldenrods. However, their low frequency of interplant movement greatly reduces their effectiveness. Primack and Silander (1975) showed that honeybees were far more effective pollinators of Oenothera fruticosa than were soldier beetles (Chauliognathus marginatus). Apis and native bees are both likely to be fairly effective pollinators of goldenrods. However, ‘épig carry larger amounts of goldenrod pollen and, except for the earliest portion of the goldenrod flowering season (containing all of g, Juncea flowering and the earliest portion of g, graminifolia flowering), honeybees are by far the most abundant visitors to goldenrod flowers. Bombus spp. and syrphid flies (Syrphidae) are very uncommon visitors to Solidago spp. in the study areas; however, authors working in different geographical areas have reported Bombus spp. (Morse 1977; Mulligan and Kevan 1973; Heinrich 1979b) and syrphid flies (L. Hermanutz personal communication) to be important visitors to Solidago flowers. Indeed, before the introduction of abundant épig papulations it is likely that Bombus and native bees were the major pollinators of Solidago. The pollination system of all four goldenrods is relatively unspecialized; insects transfer pollen from many parts of their bodies ‘as they forage throughout the inflorescences of a clone. Furthermore, ‘pollinators are frequently seen revisiting flowers in the course of a :few minutes of foraging time. It is therefore unlikely that the amount <>f pollen reaching stignas is greatly limited by behavioral 10 specializations of individual pollinators. Blister beetles, Epicauta pennsylvanica (DeGeer) (Meloidae), are common visitors to goldenrod flowers. They are flower predators, eating the anthers and stigmas from disc flowers, and occasionally eating stigmas of ray flowers. Larvae of Coleophora spp. (Lepidoptera, Coleophoridae, casebearers) feed on developing seeds of goldenrods, hollowing-out or consuming the fertilized seeds within the developing heads. Seed losses to casebearers are generally negligible, but there is great variability between years and occasionally stems may lose up to 652 of their potential seeds (Werner et al. 1980). Seeds of all four species begin dispersing approximately 5 weeks after flowering has ceased in the fall. Hereinafter ”seed” will be used in a general sense to refer to the one-seeded fruit of Solidago which is technically an achene. The seeds and attached pappi are wind dispersed; the relative dispersal capabilities of the four species are given in Herner and Platt (1976). Goldenrod seeds are mature at the time of dispersal and do not require a cold treatment to germinate in the laboratory; in the field, seedling emergence occurs mainly in early June, but continues into early July (Werner et al. 1980). Because these goldenrods initiate flowering at different times, they are exposed to different portions of an ever-changing community of flowering plants with which they may potentially compete for pollinators. I asked the following questions of each Solidago species: 1) Within a population of Solidago, does the time at which an individual (hereinafter also a clone) flowers have an effect on seed production?, 2) If the time of flowering is correlated with changes in seed production, is the pattern of seed production related to changes 11 in the visitation rates of pollinators, flower predators, or seed predators?,and 3) Is seed production limited by some factor other than the abundance and behavior of insect visitors? CHAPTER 2 METHODS Marking and Monitoring Phenology 2£_Solidago A portion of McKay Field at KBS, abandoned for 6 years, was chosen for the study; because the field was only recently abandoned, the individual clones were quite distinct and easily marked for identification. Solidago canadensis and Sf‘graminifolia were dominant members of the plant community in the portion of McKay Field utilized for this study. In order to monitor individual plants, 50 S. canadensis and 23 g. graminifolia clones were marked with numbered pieces of lath on 2 September, 1979. An additional 60 clones of S. canadensis and 26 clones of S, graminifolia were marked in early-June, 1980, well before any flowering had commenced. In each year, adjacent portions of McKay field were completely censused for Solidago clones which were marked without regard to their flowering time. Other plant species which were abundant in McKay Field included Agropzron repens (L.) Beauv., Aster pilosus Willd., A, sagittifolius Hilld., and Potentilla recta L. Clones of g, nemoralis and S, juncea were marked in a field (Louden Field) which had been abandoned from agriculture for 31 years, but had soil similar to that of McKay Field. In mid-August, 1980, 156 clones of §, nemoralis were marked with numbered pieces of yellow flagging. Solidago nemoralis clones were completely censused in two areas of Louden Field (95 and 61 clones in areas A and B, respectively); both areas had relatively dry soil and were largely dominated by S, nemoralis clones. When clones had more than one ramet (181 of the population), each ramet was individually marked, but still 12 13 identified as a member of a single clone. The average number of ramets per clone for clones with more than one ramet was 2.4; no clone had more than four ramets. In early-July 1980, 91 £3 juncea clones were marked on a relatively dry slope dominated by S3 juncea and several species of grasses (Poa spp., Phleum pratense L., AgroEZron repens (L.) Beauv.). As with S, nemoralis, ramets of S, juncea clones were individually marked, but still identified as members of a single clone. If a clone had more than 5 flowering ramets, the central 5 flowering ramets were marked; in the case of 2 large clones, the central 7 flowering ramets were marked. Because S, 122233 clones are relatively diffuse, marking the central flowering ramets was the most conservative method of insuring that marked ramets belonged to the same clone. Fifty clones had only a single flowering ramet; of the 41 clones which had more than one marked flowering ramet, the number of clones with 2, 3, 4, 5, and 7 marked flowering ramets was as follows: 11 had 2 ramets, 6 had 3 ramets, 5 had 4 ramets, 17 had 5 ramets, and 2 had 7 ramets. Although S, canadensis and S, graminifolia occur in Louden Field, the clones of these species had grown very large. Therefore, it was not possible to accurately determine the boundaries of enough clones to complete the study. Alternatively, few clones of S3 juncea or E3 nemoralis had yet invaded the younger field (McKay Field). The flowering phenology of S, canadensis and S, gggminifolia was determined by monitoring the flowering phenology of individual clones; the ramets within these clones flower synchronously. In contrast, the ramets of g, juncea clones flower somewhat asynchronously. Because of the diffuse growth habit of S, juncea clones and the asynchronous 14 flowering of ramets within clones, the flowering phenology of _S_. juncea was determined by monitoring the flowering phenology of individual ramets. Since no information was available on the relative synchrony of flowering within S, nemoralis clones, the flowering phenology foI§3 nemoralis was determined by monitoring the flowering phenology of individual ramets within each clone. At intervals of 3-8 days throughout the flowering period of each species, estimates were made of the percentage of heads (capitula) in each inflorescence which were in bud, in full flower, and past flowering. Heads were considered to be past flowering when they had only dry flowers which were unreceptive to pollen. Pollinating insects were never seen visiting an inflorescence in the past flowering stage. The percentage of heads in each stage was estimated to the nearest 5!. Inflorescences of all four species passed through the following sequence: 1) All heads in bud, 2) Heads in bud and in flower, 3) All heads in flower, 4) Heads in flower and past flowering, 5) All heads past flowering. A few S, graminifolia clones and S, juncea ramets exhibited complex flowering behavior; at a single point in time, they had heads in bud, heads in flower, and heads past flowering. Because this flowering behavior was relatively uncommon, these clones were omitted from the formal analyses which relate flowering phenology to seed set (see below). Seed Collection In 1980, seeds were sampled from the clones and ramets of each species. Two clones of S, canadensis, each having a single ramet, died before flowering and one clone with 21 ramets failed to flower; many of the buds remained unopened in this clone. Five clones of S3 nemoralis 15 died before flowering and nine ramets representing six clones failed to produce normal flowers; the flowers were small and green and the rays did not develop. Four flowering ramets of S, juncea (two were entire clones) died before flowering was complete. Solidago graminifolia had 1002 survivorship and flowering of clones. Up to 12 ramets were sampled from clones of .S_. canadensis and _S_. graminifolia to determine levels of seed production. Because clones of .S. canadensis and S, graminifolia ranged in size from several flowering ramets to over 200 flowering ramets, an attempt was made to standardize the environment in which the ramets flowered and matured seeds by sampling ramets from the outer regions of all clones. Ramets from the central region of different-sized clones could have been subjected to different environments. For example, competition for water and nutrients between goldenrods and grasses may result in strong effects of interspecific competition throughout a small clone, whereas competition among ramets of the same clone may be a more important factor in the central region of a large clone regardless of the density of grasses. In order to collect random samples of seeds, four directions were chosen (before seed collection began) relative to a road which paralleled the field; these directions corresponded to NE, NW, SE, and SW. The seeds from the three outermost ramets falling closest to each of these four directions were collected from each clone as the ramets matured. If a clone had fewer than 12 ramets, all were collected; the maximum number of ramets sampled per clone was 12. The entire inflorescence was collected at the time when most seeds were ready for dispersal. 16 In 1979, S, canadensis and S, graminifolia seeds were collected in a different manner. Seeds were collected randomly from inflorescences scattered throughout the clone; the seeds collected from different ramets were not kept separate. Other aspects of the handling of the 1979 seed collections were identical to those of the 1980 seed collections. Seeds were collected from all marked ramets of S, nemoralis and S. juncea. The seeds collected from different ramets within a clone were kept separate. Portions of S, juncea inflorescences had seeds ready to disperse at different times over a period of approximately two weeks. Therefore, seeds were collected from a single S, juncea inflorescence on several occasions over a 2-3 week period; the collections from different sampling times were not kept separate. The other three species of Solidago had the bulk of the seeds within an inflorescence ready to disperse at approximately the same time. The entire inflorescence was collected from S, nemoralis ramets at the time when the maximum number of seeds were mature and ready to disperse. To determine if clone height was related to seed set, the heights of S, canadensis and S, nemoralis ramets were measured from the ground level to the top of the inflorescence at the time of seed collection. The seeds of all four species were stored in the laboratory in paper bags. £92 _S_e_t_: Percentage 9_f_ Viable S9323 In the laboratory, seeds were removed from inflorescences by hand by gently rubbing the heads to separate the seeds from the subtending involucral bracts. These seeds were thoroughly mixed and a subsample was transferred to a petri dish. The petri dishes were then placed 17 over a numbered grid by which seeds were chosen randomly using a table of random numbers. The seeds chosen in this manner were examined individually under a dissecting microscope. At least 100 seeds which showed no evidence of predation by casebearer larvae were examined from each inflorescence. Seeds were classified as filled or unfilled after squeezing them with a pair of fine forceps. Most unfilled seeds were obviously shriveled and showed no evidence of an embryo. Some unfilled seeds were swollen but they had no embryo and were easily crushed. Filled seeds were obviously larger than unfertilized ovaries and were not crushed when pressure was applied with the forceps. The number of seeds which were filled and unfilled was recorded for each inflorescence along with the number of seeds showing evidence of predation (seeds were hollowed-out or partially consumed). Seeds from disc flowers which had failed to open and the few seeds which had been severely attacked by fungi were completely excluded from the analysis. The germinability of filled and unfilled seeds of S, canadensis was tested to determine if the method used to distinguish filled seeds effectively distinguishes between viable and inviable seeds. The percent germination for filled and unfilled seeds of S, canadensis was determined in 1979 by placing lots of 50 filled and 50 unfilled seeds in petri dishes with 4 ml of distilled water (water was then added as needed). Before being placed in the petri dishes, the seeds were soaked for approximately 30 seconds in a 10% solution of Chlorox and then rinsed with distilled water. Eleven lots of unfilled seeds and six lots of filled seeds were placed in a growth chamber set for 14 hr of light at 75°F and 10 hr of darkness at 45°F. Germination was scored as the emergence of the radicle from the seed cost. After 21 days, 18 unfilled seeds had 0.2 i 0.62 (x 1- SD) germination while filled seeds had 46.2 1:14.21 germination. Both groups of seeds suffered from fungal attack, but the incidence of attack was more frequent and more severe in the seeds classified as filled. Furthermore, there was very little overlap in the distributions of weights of filled and unfilled seeds (Figure 1). These results demonstrate that the method used for determining filled seeds effectively distinguishes between viable and inviable seeds. The percentage of filled seeds will be used as an estimate of seed production per flower in goldenrod ramets. Of the 12 ramets collected from clones of S. canadensis and S. graminifolia, eight were selected for determining percentages of filled seeds. If all 12 ramets were collected on the same date, eight ramets were randomly selected from the entire group. If the 12 ramets were collected on more than one date, ramets were selected randomly from within each collection date such that the range of collection dates was represented in the eight ramets chosen for analysis. (It was subsequently found that within a clone the date of seed maturation was not correlated with the percentage of filled seeds on the inflorescence.) To maintain a sample size of eight ramets per clone for S. ‘graminifolia and S, canadensis, 54 clones of S, canadensis and 44 clones of S, graminifolia were chosen for analysis. These clones were chosen to represent the range of flowering times within the populations. They also included all clones which had received experimental crosses (see below). Seven clones of S, graminifolia were eventually excluded from further analyses because of their complex flowering behavior. The percentage of filled seeds was not determined Figure 1: 19 Frequency Distributions of Heights of Filled and Unfilled Seeds of S, canadensis. The weight classes (A - P) represent 0.010 mg increments in seed weight. Absolute seed weights are not reported because weights were originally obtained using an improperly-calibrated balance; the relative positions of the distributions for the two seed classes are correct. The mean weight of filled seeds has subsequently been found to be 0.083 mg per seed; unfilled seeds have a mean weight of approximately 0.019 mg. 1% WW (1) SEED WEIGHT (mg per see /<, o o o o , n N '- 90339 :10 USBWDN 21 for approximately 10% of the S, juncea ramets because seeds were collected before they had matured. Approximately 252 of the S, nemoralis ramets were not analyzed for the percentage of filled seeds because many ramets were collected after most seeds had dispersed and some ramets appeared to have been attacked by an herbivore which had webbed heads together, thereby making it difficult to remove seeds. The omission of ramets from analyses was not biased against clones which had flowered in any particular portion of the flowering season. Seed Set: Total Production To obtain a measure of the absolute number of seeds produced per inflorescence the total volume of seeds and associated involucral bracts and flower parts was measured for each ramet. The seeds from each ramet for which the percentage of filled seeds was known were placed in 40 ml beakers and the volumes were estimated to the nearest 10 ml. Because these measurements were taken after the estimates of seeds were obtained, ramets had lost variable portions of their total seed production. These losses were, however, most likely randomly distributed among clones or greatest in the clones with the largest total seed volumes (thereby biasing against finding differences among clones). Therefore, estimates of total seed production for groups of clones flowering at different periods of the flowering season should not be affected by the loss of seeds from some clones, or will be biased towards not finding differences in total seed production for the different groups. The volume estimates were not calibrated for absolute numbers of seeds and therefore serve only as relative measures of potential seed production among clones within a species. 22 FloweringPhenologygg£_0ther Species To investigate the potential for competition for pollinators between goldenrods and other plant species in the surrounding communities, flowering phenologies were recorded for most of the common insect-pollinated species in the summer flora surrounding the study sites. Table 2 lists the species investigated for flowering phenology and the location of the plots used for the study; it also indicates the morphological unit used to quantify the flowering phenology of the different species. Phenology measurements were begun at or before the peak of flowering for the species in Table 2. With the exception of Aster pilosus, these species were all introduced from Europe and they flowered abundantly throughout the summer. Aster pilosus is a native member of the fall flora. Insect Sampling To determine if members of the plant commnity listed in Table 2 were attracting the same insects as Solidago spp., the insects visiting these the percentage of filled species were censused by visual counts (_C_. arvense, A. minis), by sweep samples (Li, 5.1.1193 _C, maculosa, A. pilosus , or by timed searches where a sweep net was used to collect all the insects observed visiting the plants (I, pratense). Sampling was poorly standardized among species, but the data do provide a relative measure of the abundances of different insects on plant species in the summer and fall flora. The variation in the growth habit and the insect visitors of the different goldenrods made it necessary to use various techniques for sampling insects (Table 3). However, the sweep samples and visual counts of insects from S, graminifolia and S, canadensis clones are 23 .mowooom some you voxuma no: mucmua no macaw msoonowoao: .owumH o um:u £05m voomam one: boxy “moose new swam 0» economy now: ofinmuum> who: macaw a .muomouu mono cows masuqmmo .oz .muosoam ammo suds mooeoomouoamow .oz .muomoaw mono no“: mooaoomouoamcu .oz .muo3oaw mono nuuz masuwmmo .oz .muo3oHu cons to“: masufimmo .oz .muosoau mono :uas moocoomouoauaw .oz .muoaoau mono nous manuammo .oz .VHouu vocovmmnm vHOIumoh m .vaouu vocovcmpm vHqumoh mu .vaofim vocovcmpm vacuums» mu .vaoum vocovcmpm vHOIumoh mu .maowu mosovcmnm vHqumoh mu opwmvmou posoaca owwmwoou peso: vaoqm vocovcmnm vacuumoh mm mowmvmou vo3oz moumm Sumo: moans uo>oHo moans uo>oHo pox magmanu eases xoovusp coaaou uo>oHo momma sauna voosomcx vouuomm .mfiawa msooawm noum< .A common .M .A omsouomm‘asuaouuua .noom A.Av omno>um sausage .eanom Aaaumv sagas asauuu< .umon spam mouoawfloz oafld ”OOH—dug GUN—JOUCUU pompous: uacs docuumaamom uo scuumooa mamz coaaoo mouoomw o>quo= m mu msmoaum noum< couscouucu Ham who omosu .msmonm a«_uou umooxm cu mucmam wouumu>loom :oEEou any you moaonocosm wcuuoonm mcucaeuouoa now ovozuoz .muon aamu ago we moose: .ooessm oxu usozwsouzu maucmmcspo upsoau gums: mouoomo .mmou< zmsum may no huucuoa> ego ”a .os.a 24 Table 3: Methods and Dates for Insect Samples from Solidago spp. Collected During the Fall and Summer 1980. Species Sampling technique Range of Samling Dates Solidago graminifolia Sweep sample; total of 20 Aug.-2 Sept. 10 sweeps from 6-8 clones. Visual counts on clones. 12 Aug.-17 Sept. Solidaggcanadensis1 Sweep sample; total of 24 Aug.-23 Sept. 10 sweeps from 6-8 clones. Visual counts on clones. 23 Aug.-30 Sept. Solidaggjuncea2 Timed search with sweep 29 July-18 Aug.3 net; approx. 15 flowering ramets sampled each period. Solidago nemoralis Sweep sample; 1 sweep 3 Sept.-18 Sept. from each of 50 flowering ramets. l Insect data are reported for both S, canadensis var. scabra and S. canadensis var. canadensis. 2 Only bees and wasps were sampled relative to their abundances. Beetles were collected in very small numbers only to document that they were present on S, juncea on that census date. 3 Entire flowering season was not included in the samples; flowering occurred until late-August. 25 directly comparable between species and also permit comparisons between techniques. The only major difference between the sweep samples from S, nemoralis and those from the above species is the number of ramets sampled per sweep. The sampling technique used for S, juncea was, however, quite different from the techniques used for the other goldenrods. At minimum, the insect samples collected from the goldenrods permit comparisons of insect abundance within each species over its flowering period. All visual counts and sweep samples of insects were performed between 1330 and 1630 hours. This is approximately the period of maximum insect abundance (especially for honeybees) on S, canadensis and S, graminifolia (Figures 2 and 3); Ginsberg (1979) reports maximum numbers of Apis mellifera on S, juncea between 1400 and 1600 hours. Visual counts of visitors are very easily obtained for large insects such as honeybees, wasps and beetles. Except for Bombus spp., most native bees (i.e. Ceratina) are too small and move to rapidly to census by visual counts. Therefore, data from visual counts of visitors is used to quantify visitation rates of only the larger insects. For all censuses performed by sweep samples, the insects were placed in a killing jar and brought back to the laboratory for identification. Crossing Studies: Compatibility Experiments To determine if goldenrods could produce seed in the absence of pollinators several inflorescences from each of several clones were bagged in the bud stage with 1 mm nylon mesh bags which excluded all potential pollinators. Thin metal wire was threaded through the bags and tied to bamboo stakes; this supported the flowering ramet and prevented the bag from contacting the enclosed open flowers. Two Figure 2: 26 Total Numbers of Chaulioggathus and A218 Counted During Visual Censuses Over the Course of One Day on S, canadensis. Counts were made on six clones of S, canadensis var. scabra and four clones of S, canadensis var. canadensis. The census was conducted on 3 September, 1980. INSECTS TOTAI. 27 O—-0 Solidogo canadensis var. scabra 120 ."". Solidogo canadensis vor. canadensis Chauliognathus 100 80 so \ Apis 40 ’,A\ /' I. ) v“.\. 0.. — * Ir. \.\. 20 °’ "’o I ' . ' ,a”.' \éhouliognothus I. .” A13is ‘x, o I \ J 0’. .\. O . 0920- 1043- 1227- 1433- 1637- 1832- 0943 1123 1310 1513 1712 1859 TIME OF DAY Figure 3: 28 Total Numbers of Chauliognathus and Apis Counted During Visual Censuses Over the Course of One Day on S. graminifolia. Counts were made on four clones of S. graminifolia. The census was conducted on 3 September, 1980. INSECTS TOTAL 140 120 100 80 60 40 2O 29 §_. grominifolia Chauliognathus 0930- 1102- 1252- 1455- 1657- 1845- 0940 1123 1310 1513 1712 1859 TIME OF DAY 30 additional treatments were performed on bagged inflorescences to test for self-compatibility. Crosses were performed between ramets from two different clones (outcrossing) and between ramets from the same clone (selfing). This experiment tests for the ability to self-fertilize in the presence and absence of pollinators. Grosses were performed on four heads per treatment. Pollen was obtained for crosses by bagging inflorescences several days before performing a cross and using the dehisced anthers from the bagged inflorescences as brushes for applying pollen. Because it was much easier to pollinate the stigmas of the ray flowers before the disc flowers were receptive, only ray stigmas were utilized in all crossing experiments. Furthermore, Delisle (1954) found that controlled pollinations of ray and disc flowers of Asters gave mch higher production of fertile achenes from ray flowers. He suggested that only ray flowers be used for the female parent in controlled pollinations in Asters. Pollen could be applied accurately to the stigmas by holding the dehisced anthers with a pair of fine forceps. This technique for pollinating the small flowers of composites is more reliable than rubbing heads together to transfer pollen to receptive stigmas (R. C. Cruden, personal communication). The heads (capitula) in which flowers were crossed were marked with strips of colored flagging. Crossing Studies: Pollination Versus Physiology To control for possible physiological or environmental causes for ‘variation in seed production over the flowering season, experimental crosses were performed on Solidago clones which flowered at different times during flowering season. Twa treatments were used. BAG CROSSES were made in _S_. canadensis and S, graminifolia. This treatment 31 consisted of pollinating the ray stigmas in each of four heads on two inflorescences per clone which had been bagged in the bud stage with 1 mm nylon mesh bags. OPEN CROSSES were performed on S, canadensis, S, jgraminifolia, and S, juncea. This treatment consisted of pollinating the ray stigmas on each of four heads per inflorescence (two inflorescences per clone for S, canadensis and S, graminifolia) which were left exposed to the environment. The control for changes in the amount of self fertilization over the flowering period (BAG CONTROL) consisted of the part of the inflorescence that was bagged, but not pollinated, in the BAG CROSSES. As before, pollen was obtained from the inflorescences of donor clones which had been bagged in the bud stage. No experimental crosses were performed on S, nemoralis. In most cases, all four heads which received experimental crosses were collected from each ramet. When both replicates (i.e. both ramets with crosses) survived the season (stems were sometimes broken by wind damage), the average of the two was used as the percentage of filled seeds for each crossing treatment per clone. Because seeds often fell out of heads in storage, it was not usually possible to determine seed set per head; the percentage of filled seeds was calculated from the total number of filled seeds and the total number of seeds in the four heads used in each cross. Along with the crosses, the rest of the bagged inflorescence was collected as the control (BAG CONTROL). When the seeds from the experimental crosses were counted, it was often impossible to differentiate with confidence the seeds from ray and disc flowers. The percentage of filled seeds from each cross was initially corrected to account for the fact that ray flowers (used in the crosses) represented 80% of the total flowers per head. However, 32 the correction had to make the assumption that disc and ray flowers had equal probabilities of forming seeds. If ray flowers formed more seeds than did disc flowers (on a per flower basis), then the correction overestimated the seed set of crosses relative to untreated clones. In fact, it was noted that ray flowers appeared to have had much greater seed set relative to disc flowers under natural conditions. Therefore, it was concluded that the data from the crosses were most comparable to the percentage of filled seeds in untreated clones if no correction was made for pollinating only ray flowers; all data reported for the experimental crosses are uncorrected. If any bias is introduced by not correcting the experimental crosses, it is in the direction of underestimating the seed set of the crosses, thereby biasing against finding differences between the seed set of the crosses and that of the untreated clones. CHAPTER 3 RESULTS Compatibility,Experiments All four species of Solidago are largely self-incompatible and require a pollinator for successful seed set (Table 4). The crosses performed within clones (selfing) did not give significantly higher percentages of filled seeds than flowers which received no crosses; both treatments yielded significantly lower percentages of filled seeds than the outcrossing treatment. Although the appropriate experiments were not performed on S, juncea, the low levels of seed set in the absence of pollinators suggests that it too is self-incompatible. FloweringgPhenology Solidago juncea flowered earliest and its flowering period overlapped very little with those of the other goldenrods (Figure 4). Over 802 of all S, juncea ramets were largely past flowering by the time S, graminifolia reached peak bloom (compare Figures 4 and 5). Solidago graminifolia was at peak bloom approximately 7-10 days before S, nemoralis and S, canadensis reached the peaks of their flowering periods. At this time, almost 701 of the S, graminifolia clones were largely past flowering. The flowering periods of S, nemoralis and _S_. canadensis exhibited almost complete overlap. The same sequence of flowering observed for these four species of goldenrod in 1980 has also been reported in different years from New York State (Hurlbert 1970; Ginsberg 1979). It therefore seems likely that these species retain the same sequence of flowering throughout mch of northeastern North America. Individual clones and ramets of all four species had at leat 402 33 Table 4: 34 Percentage of Filled Seeds from Compatability Experiments. Values are mean percentages of filled seeds. The values in parentheses are the 95% confidence intervals and the number of inflorescences per treatment. Except for selfing in _S_. ‘graminifolia, the treatments were performed on bagged inflorescences in at least six different clones. Means and confidence intervals have been backtransformed following angular transformation. different letters are significantly different at P < .01 by Tukey's Test after analysis of variance on angular transformed data. Means in each row followed by No Cross Selfed Outcrossed Solidago graminifolia 2.15a 3.26a 78.52b (0.13 - 6.55) (0.04 - 11.26) (64.63 - 89.69) (6) (3) (9) Solidago nemoralis 1.20a 8.02a 55.22b (15) (8) (8) Solidagg canadensis 2.77a 4.478 65.65b (10) (6) (9) Solidago juncea 0.00 ---- ---- (0.00 - 0.00) (6) 1 No compatability experiments were performed on S, juncea except for bagging inflorescences with no crosses. filled seeds from the OPEN CROSSES on S. (7.66-18.60; 28) (952 Confidence interval; N . The average percentage of juncea was 12.62 Figure 4: 35 Flowering Phenology of Four Species of Solidago in 1980. The percentages of clones (S. canadensis, S. raminifolia) or ramets (S. nemoralis, S. —juncea) with at least 0 all heads (capitula) in flower are plotted against census dates. The phenology data from S. canadensis include data from 21 clones of S. canadensis var. canadensis and approximately 100 clones. of S, canadensis var. scabra. The number of clones or ramets censused on any given date for the other species corresponds approximately to 59 clones of S. 'graminifolia, 190 ramets (156 clones) of S. nemoralis, and 205 ramets (90 clones) of S. juncea. 36 «map—OOH «maimhdmm H hm303< H 53—. n m m 0 V n— m mm mm a. m.— ou Va 2 3 on ma om - c on CV 00 «20350: .m «.10 323.353 .m I 0:03.:an .m 010 0m 0025.. .m I oo— USMO'IJ NI V'InlIdVD TIV :10 012 HllM SlBWVU 210 SBNO'ID :IO 39V1N3383d Figure 5: 37 Cumulative Frequencies of Clones or Ramets Largely Past Flowering for Four Species of Solids o in 1980. The cumulative frequencies of clones (or ramets) with at least 702 of all heads past flowering are plotted against census dates. The numbers of clones and ramets used are given in Figure 4. A separate curve has been plotted for S. canadensis var. scabra. _- 38 zmehUO «— n «maimhmmm mm mm m— m— n hm303< 53.. omwm 2: o Vomnmom nzocoEoc .m 410 1.9.0 0303 .53 333553 .m 0:... 3301.055 .m I 0:035:55 .m 010 5.5.2:‘ .wI o O N O V 9NI83MO'IJ lSVd v1nudv3 11V 50 96022 HllM SLBWVH 80 SBNO'ID :IO 39V1N3383d O 0 O o co— 39 of all heads in flower for a period of approximately 10-14 days. Because of this extended period of flowering, few (< 202) of the clones and ramets of each species were more than 702 past flowering when their populations were at peak bloom (Figures 4 and 5). Although the bulk of the clones and ramets completed flowering just after peak bloom, a number of late-flowering clones and ramets continued flowering for another 1-2 weeks. Within each population of goldenrods, there was a great deal of variation among the flowering phenologies of individual clones of S. canadensis and S. graminifolia and ramets of S. juncea and S. nemoralis. Although the length of the flowering period was similar for most clones and ramets, there was much variability in the date on which flowering was initiated. When the populations were near peak bloom, it was possible (on any given date) to find early-flowering clones and ramets which were largely past flowering, intermediate-flowering clones and ramets which were in full flower, and late-flowering clones and ramets which were still in bud or which had barely begun to flower. Both S, canadensis and S, graminifolia flowered earlier in 1979 than in 1980. In 1979 the cumulative frequency curves of the percentage of S, graminifolia and S, canadensis clones which were largely past flowering fall above similar curves for 1980 (Figure 6). Earlier flowering in 1979 was more pronounced for S, graminifolia; over 702 of all clones were largely past flower in 1979 on the date (3 September) which approximately corresponds to the peak of the 1980 blooming period. Although there was between-year variation in flowering phenology within the population, there was also a highly significant positive correlation between the relative order of Figure 6: 40 Cumulative Frequencies of S. graminifolia and S. canadensis Clones Largely Past Flowering in 1979 and 1980. The cumulative frequencies of clones with greater than 702 of all heads past flowering are plotted against census dates. The curves for S. canadensis contain 5 and 21 clones of S. canadensis var. -canadensis and 45 and 100 clones of S. canadensis var. scabra, respectively for 1979 and 1980. The curves for S. graminifolia contain approximately 20 and 59 clones, respectively for 1979 and 1980. 41 O S. grominifolio O S canadensis O O O O O Q 0 V N ONIUBMO'IJ lSVd SOVBH ‘I'IV :IO %O£< HllM SSNO'ID :IO 39V1N3383d 10 15 I9 23 27 30 SEPTEMBER 11 42 flowering of S, canadensis clones in 1979 and 1980 (Kendall's coefficient of rank correlation, T - 0.50, p < .001). Early-flowering clones of S, canadensis tend to flower early every year; intermediate- and late-flowering clones also show great between-year consistency in their relative flowering times. Construction 2£_phenology groups: The clones or ramets of each species were assigned relative phenology ranks based on their stage of flowering on the 1980 census date that showed the greatest variability in flowering phenology among the clones or ramets. Using the flowering phenologies recorded on this date, the clones or ramets were ranked from the earliest-flowering clones or ramets with the greatest percentages of heads past flowering to the latest-flowering clones or ramets with the greatest percentages of heads still in bud. Any clones (or ramets for S, juncea and S, nemoralis) which were tied for the percentage of heads in the bud, flowering, and past flowering stages were assigned the same rank. (Average ranks were assigned for nonparametric correlation analyses.) The census dates with the maximum amount of variability among the flowering phenologies of clones (and ramets) corresponded well with the peak of the flowering period for each species. The census dates used for the four species were 13 August for S, juncea, 28 August for S, graminifolia, 10 September for S, canadensis and 13 September for S, nemoralis. To perform statistical annalyses on differences in seed production over the flowering season, the clones (or ramets) of S, canadensis, S, juncea, and S, nemoralis were divided into three phenology groups -- Early (E), Intermediate (I), and Late (L) based on the relative 43 phenology ranks previously assigned to the clones and ramets of each species. Solidago graminifolia clones were divided into two phenology groups, Early (E) and Late (L), because the number of clones with estimates of percentages of filled seeds was not adequate to perform statistical analyses on three classes. Phenology groups were formed such that the number of clones (or ramets) in each group and the number of ranks assigned to each group were approximately equal among the phenology groups. Clones and ramets were assigned to phenology groups without regard to their percentages of filled seeds. Differences in the mean percentages of filled seeds among the E, I, and L phenology groups were discerned by Tukey's Tests for all possible comparisons among means following one-way analysis of variance. Statistical analyses performed on percentages were preceeded by angular transformation of the data (Sokal and Rohlf 1969). Spearman rank correlations were performed between the relative phenology ranks and the percentage of filled seeds per clones or ramets. For the 1979 data, S, canadensis clones were chosen to represent three distinct phenology groups. The percentage of filled seeds was determined for each clone after phenology groups were assigned. The census date used for placing clones in E, I, and L phenology groups was 6 September, 1979. Relationships 2; Phenology Groups 52 Seed Set: There were significant differences in the percentage of filled seeds among the phenology groups of each species (Table 5). Early-flowering clones (or ramets) had significantly lower percentages of filled seeds than the late-flowering clones (or ramets) in S, canadensis, S, graminifolia, and S, nemoralis (Table 5, Figures 7, 8, 9). The same result was 44 “Show “one akev Ammo ka.e_ - he.oiv Awe.» - ok.mV Ace.~_ - me.o~v Amo.s~ - mm.m_v ee.- amk.n ask.n~ ume.a~ «ocean owneaaom Awe A v x~a.m~ - o~.wv muse mm.k~ -- -- -- «Haemaefiammu_ouueaaom Reno az~v memo x~m.os - me.m~v Ao_.ae - ~k.mmV A-.sm - im.o_~, “owa_v as.em nmm.~s -- «Nm.m~ «geomacaaouw ouaeumom asNEV Amsv AosV azsv Ais.om - m~.auv Amm.ms - sm.~mV a~e.Ns - oa.e~v Amo.~m - am.aav ek.~m nom.kn aoa~.mm ¢e~.m~ sameness: owweaaom “one Ammo ammo Ase ASN.o~ - om.ko Am~.wm - am.oiv Awa.- - no.mv Amm.o - mo.ov Amkoav mN.n~ nom.- paeo.m_ aeo.~ naucoeucau owneaaom Acme As_v AmNV Am_v Ami.mm - mm.w~v a~m.~m - mm.mmV Am~.me - om.imV Aom.k~ - mm.~uv moms—N e~.mm nos.~s na_.en aoe.o_ sesameocuu o negaom aa< a H u I||II .mump coauoumcmuu umaswcm co oocmuum> mo mamhfiocm moumm umoa m.%oxoh he Amwaouoao: .m.v=o mna— .mamsopmcmo am.uom mc. v my me. v m on ucououuwp maucmowuecwwm one muouuoa ucouomuav up moaoaflou sou comm ca memo: .couumaooumsmuu umfismcm wousofiaou moEuOumcmuuxoon coon o>ms m~o>uoucw oocovawcoo pom memo: .esouw mwoaocone some a“ moose» no mocoao mo oneness o;u pom mHm>uou:« menopaucoo Nmm osu mum monogamoumm cu mo=Ho> one .ovooo poaaam mo mowmucoouod some mum mosao> .mdsouc aonososm mama pom .oumuvoeuousw .haumu :« uoamu no ocoao use ovoom voaauh mo owmucoouom um mange 45 Figure 7: Percentage of Filled Seeds Versus the Relative Phenology Ranks (1 - 23) of S, canadensis Clones in 1980. The continuum of phenology ranks is divided into the three phenology groups. The percentages of filled seeds have not been subjected to any transformations. For the figure, ties were assigned to the same rank, and ranks were numbered consecutively. 46 canadensis s, mammm 03...”. “.0 m0 no mammfimso momma amok n.5oxsh me no. v e um acouowuav mHusoouuacwam sum muouuoa acououmap ma posoafiou sou sumo cu memo: .coqumauoumcouu umfismcm wcasoaaou voEHOumcmuuxoma coon o>mc mHm>uoucu menopausoo was memo: .osouw mwoaocone some cu mucous mo hopes: ox» was Ho>uoucu oocovaucoo Nma on» one monotonouom cw mooam> any .mvoom moaaum uo mowoucooood some mum mosam> vouuomox .msouw mmoaocozn oaom osu cw voomam was: even: ocofio oawcam a as nausea you powmuo>m one: spoon vouauu uo mowmucoouom och .vouoaom who: macaw mmoaoconm moo away who: sued wcufiamu museum god: mocoao .masouo honococm sum; was .mumuvoEuoucu .hauom ca ocoHo use ovoom voaaam mo owmucoouom um manna 56 it is also important to determine if there were differences in the total numbers of seeds produced by early-, intermediate, and late- flowering clones. Table 7 gives the average volume of seeds per ramet for all four species of goldenrod. There was no difference in the volume of seeds per ramet for the E and L phenology groups in S. graminifolia. Neither was there a difference in the number of ramets per clone in the E (85 i 25) (X i 952 conf. interval) and L (66 i 25) phenology groups (P > .20, one-way analysis of variance). The difference in percentage of filled seeds per ramet therefore corresponds to real differences in the total numbers of seeds produced by clones in the E and L phenology groups. Solidagg canadensis and S, nemoralis had significantly smaller volumes of seeds per ramet in the E phenology group. And again, there was no significant difference (P > .20, one-way analysis of variance) in the number of ramets per clone in the E (58 i 21) (X _-_I-_ 952 C.I), I (59 i 19), and L (50 i 18) phenology groups of S, canadensis, or S, nemoralis (ramets/clone: E - 1.2, I - 1.1, L . 1.3). These results mean that the negative correlation of percentage of filled seeds with early-flowering in S. canadensis and S. nemoralis is amplified in total seed production which was substantially lower in the early-flowering clones. Similarly, 1“.§f juncea the late- flowering ramets, which exhibited the lowest seed set per flower, also had the lowest total number of filled seeds per ramet. Although there was a great amount of variability among clones and ramets with respect to the percentage of filled seeds in 1980 (Figures 7-10), it is important to note that, at least for S, canadensis, individual clones show great consistency between-years with respect to their relative phenology ranks and relative percentages of filled Table 7: 57 Intermediate, and Late Phenology Groups. volumes of seeds. inflorescence for S. Volume (ml) of Seeds Produced per Inflorescence in Early, Values are mean The mean volumes of seeds per canadensis and S. graminifolia are based on mean voluEes per inflorescenEe for each clone obtained from volume measurements on eight ramets per clone. The values in parentheses are the 952 confidence intervals and the number of clones or ramets from which volume measurements were obtained. Means in each row followed by different letters are significantly different at P < .05 by Tukey's Test after analysis of variance. E I L Solidago graminifolia 85.2a ---- 66,48 (13 clones) (15) Solidaggcanadensisl 77.8a 112.4b 141.7b (15 clones) (24) (14) Solidagg nemoralis 15.5a 21.0ab 27.2b (40 ramets) (40) (45) b be Solidago juncea 8.3ac 12.2 11.4 (56 ramets) (69) (57) 1 Means and confidence intervals backtransformed after logarithmic transformation performed to remove heterogeneous variance prior to analysis of variance. 58 seeds. As previously mentioned, there was a highly significant, positive correlation betweeen the relative phenology ranks of S. canadensis clones in 1979 and 1980. Furthermore, chi-square analysis showed that S, canadensis clones tend to be classified in the same phenology group (E, I, or L) between-years (x2 I 15.17, df I 4, P < .01). In addition, after log transformation to remove nonlinearity, there was a highly significant correlation between the percentage of filled seeds per clone in 1979 and 1980 (Pearson's product-moment correlation, r I 0.78, P < .001). Whether the effect is due to genetic determination of flowering time, innate potential for seed production, or responses to microsite differences among clones, the flowering phenology and seed set of S, canadensis clones remain consistent between years. Patterns 2S Insect Abundance There were two peaks of insect abundance on S, graminifolia (Figure 11). Beetles (Chauliognathus pennsylvanicus and Epicauta pennsylvanica) were abundant on S, graminifolia in lateeAugust, their numbers declining rapidly in early-September. Peak beetle densities were followed by an increase in the number of honeybees (Apis mellifera) visiting clones of S, graminifolia. Native bees (mostly Ceratina spp. and Halictus spp.) declined in abundance from lateeAugust through early-September (Figure 12), and, although sweep samples were not taken past 2 September, 1980, field observations indicated that the trend in decreasing abundance of native bees continued into September. Throughout September, _A_pig were by far the most abundant visitors to S. ‘ggaminifolia. Wasps were very uncommon visitors to S, 55aminifolia. The relative abundances of different insect species visiting S, 59 canadensis var. canadensis and S, canadensis var. scabra were similar to those found for S, graminifolia (Figure 13). The early portion of the flowering season was dominated by soldier beetles (Chaulioggathus , which declined in abundance throughout September. Blister beetles (Epicauta) showed a small peak in early-September, but remained at relatively low densities throughout the summer and early-fall. ‘épig began visiting S, canadensis in late-August, and by early-September honeybees were by far the most abundant visitors to S, canadensis clones. Solidago canadensis var. canadensis, which flowers before S. canadensis var. scabra, was mainly visited by native bees and soldier beetles (Figure 14). Solidago canadensis var. scabra began flowering in early-September and had S£$g_as its most abundant visitors. Wasps (Polistes spp.) were not very abundant visitors at any point during the flowering season of either variety of S, canadensis. Solidago nemoralis flowers simultaneously with S, canadensis var. scabra (hereinafter S, canadensis), and after the earliest portion of the flowering season, it too had Spig as its most abundant visitor (Figure 15). Solidago 123252, which flowered much earlier than the other goldenrods, was visited exclusively by native bees and beetles. In the study areas, honeybees were never captured on S, juncea inflorescences and in many hours of observation, Sail were never seen visiting S. juncea. Soldier beetles and blister beetles showed marked temporal patterns of abundance. Both beetles began visiting S, juncea on 8 August, 1980 and were relatively common visitors by 12 August (see p. 83). Although soldier beetles (Chaulioggathus pennsylvanicus) are 6O probably not very effective pollinators (see Study System), blister beetles (Epicauta pennsylvanica) are effective flower predators and it is possible that late-flowering S, juncea clones faced heavy flower predation. This aspect of the floral biology of S, juncea will be discussed in more detail. Because honeybees are the major pollinators of three species of Solidago which have overlapping flowering periods, it is important to note that individual honeybees show a great deal of constancy to individual species of goldenrods. Ginsberg (1979) found that honeybees almost never moved between goldenrod species when foraging in mixed stands of S. altissima (- S. canadensis var. scabra), S. rugosa, and S. graminifolia. In the study areas at KBS, honeybees were rarely seen moving between different species of Solidago. Early-flowering clones of S, canadensis var. scabra flowered at the same time as clones of S. canadensis var. canadensis. These varieties do not hybridize (R. Gross unpublished data) and the extent to which honeybees and native bees discriminate between these two varieties is unknown. The overall pattern of insect abundance on goldenrods in 1980 has also been reported in New York State by Ginsberg (1979). He found that wild bees (- native bees) were most common on the early-flowering S. juncea, while honeybees were more abundant on S. altissima and S. rugosa which flowered in the late-summer and early-fall. In some years, S, juncea was visited by Apia, but the later-flowering goldenrods (including S, graminifolia) always received substantially greater proportions of their total visits from honeybees (Ginsberg 1979). 61 Figure 11: Total Numbers of Major Insect Visitors Counted During Visual Censuses of S, graminifolia Clones in 1980. 62 k— n— amniwhmwm e on ma hm303( ON 0— «— oSouiw d .ofOcuozsosu o 3.? o .- Do. I 00a I can T 00‘ 1 ooh I 000 53133115 113d SIDSSNI 1V101 63 Figure 12: Total Numbers of Major Insect Visitors Collected During Sweep-Sample Censuses of S. graminifolia Clones in 1980. TOTAL INSECTS PER 10 SWEEPS o o J a. O J N O l 64 Solidago graminifolia O Apis o l O Chauliognathus 0 Native bees o 9 ° ~ - o . 94" o T I 1 I 1 1 j 20 22 24 26 28 30 1 3 5 AUGUST I SEPTEMBER Figure 13: 65 Total Numbers of Major Insect Visitors Counted During Visual Censuses of S. canadensis Clones in 1980. The counts are totals {Eon 21 clones of S, canadensis var. canadensis and approximately 100 clones of S, canadensis var. scabra. 66 «unsaf— mm 0— N— —n hw303( km 2:03am «can; 3583.320 .22 mm .04Q 00— com com com com SBIDSdS 113d SLDBSNI 'IVlOl Figure 14: 67 Total Numbers of Major Insect Visitors Collected During Sweep-Sample Censuses of S. canadensis Clones in 1980. The numbers of insects collecEed from clones of S, canadensis var. scabra and S, canadensis var. canadensis are reported separately. The range of sampling dates for the two species reflects their relative flowering phenologies. awnimzmm H hm303< VN ON 0. N— a V _n nu ma mun-t 5 II. 0 I ‘ s 'I 0' .II‘ | I I, I ' T 1... -e....-. - - .. , I. \ 1.0.. ....... ”1.2.8.0 O o\ ’0 z. . a. . I o’ I‘ II ‘o‘.. ’ 0.0‘I‘I o‘ 8 a .\ 6 .\ I .\.\ I .\.\ O\ 1.4 I «one; 010 To 32. 3:02 01.0 0.10 3:333:25 Or... I £Q< p.303 «_ucomocg but"; but? «_ncopocOu muolpgdw O— on On 0V on SJSSMS OI 113d SIDSSNI :IO USEWI'IN 69 Figure 15: Total Numbers of Major Insect Visitors Collected During Sweep-Sample Censuses of §, nemoralis Ramets in 1980. NUMBER OF INSECTS PER 50 INFLORESCENCES 20 18 lb 14 12 IO 70 Solidago nemoralis O 0 O A Apis Native bees Chauliognathus Wasps 9 ll SEPTEMBER 13 15 l7 l9 71 The Relationship Between Seed Production.22d Insect Abundance Because differences in total seed production per ramet and per clone were correlated with differences in the percentage of filled seeds over the flowering season, the relationship between insect abundance and seed production will be discussed in terms of percentages of filled seeds; that is, seed set per flower. In order to relate seed production to temporal changes in insect abundance, seed production must be expressed as a function of absolute dates instead of relative phenology ranks. This was done for each clone by determining on which of the 5-10 census dates a clone (or ramet) had its maximum percentage of heads in full flower; this date was designated as the maximum flowering date (MFD). After each clone or ramet was assigned to an MFD, the mean percentage of filled seeds was calculated for the clones and ramets within each MFD. Clones and ramets from the same phenology groups (E, I, or L) were usually assigned to the same -- or adjacent -- MFD. Because épig were the most abundant visitors, and probably the most effective pollinators on §_. nemoralis, _S_. canadensis, and _S_. ‘graminifolia, the mean percentage of filled seeds on each of the MFD's for each of the species was compared to the abundance of honeybees. The visual counts of honeybees on clones of g, candadensis and §3 graminifolia were considered to be the best estimates of honeybee abundance on the study sites. However, the total number of épig on the goldenrods (Figures 11 and 13) was a function of the number of clones in flower at different times within each population. To produce an estimate of the number of épig_available per flowering head for each date of the flowering season for both _S_. canadensis and _S_. 72 graminifolia, the following equation was used: n 2 “13 i - 1 Total number of Apia A3 - ; Fini -Estimate of the total 1 - 1 number of open heads where: Aj - an estimate of the number of Apig_per flowering head on date 1 N11 - number of Apig on clone 1 on date j, F13 - proportion of total heads in flower in clone 1 on date 1, R1 - number of ramets in clone 1, and n - total number of clones per species. Two patterns emerge. The first is that the mean percentage of filled seeds increased or decreased monotonically over the flowering season in each species (Figures 16, 17, 18, 19). The highest seed set per flower did not occur when the majority of the clones were in full flower. This pattern is not particularly obvious in g, nemoralis, but this is mostly due to the small number of census dates for this species. The late-flowering g, nemoralis ramets -- which had the higest percentages of filled seeds --could not be assigned to MFD's later than 18 September; therefore, a large part of the flowering period could not be represented in Figure 18. As was the case with the phenology groups, the monotonic increases or decreases in seed set per flower are either unchanged (§, graminifolia, g, Juncea) or exacerbated (§3 canadensis, §3 nemoralis) when expressed as total numbers of seeds per ramet (compare Table 7 to Figures 16-19). The second pattern is that increases in the percentages of filled 73 seeds roughly correspond to increases in Apia avilability for g. Egnadensis, S, nemoralis and §, graminifolia (Figures 16, 17, 18). (Apia availability drops rapidly on the last census date (September 23) for S, canadensis, but the percentage of filled seeds for this MFD has a huge 95% confidence interval because of a great deal of variation within the small sample of 3 clones on that date.) Additional evidence for a positive relationship between Apia avilability and seed set per flower can be inferred from the percentage of filled seeds from heads marked at different times within _S. ‘graminifolia clones. Heads which had flowered before 1 September, 1980, when Apia were not common on §,g:aminifolia, had significantly lower (P < .001)(Student t-test) percentages of filled seeds (34.13; 26.70 - 41.97; 31) (x; 952 conf. interval; N) than heads in the same clone which flowered on or slightly after 1 September (53.73; 47.00 -60.40; 31) (all values are back transformed after angular transformation). Although the insect census data from g. Juncea do not span the entire flowering season, the positive relationship between insects (here native bees) and seed set observed in the other species is not found in g, juncea (Figure 19). Flower predation by blister beetles (Bpicauta pennaylvanica) appears to have a strong influence on seed production in goldenrods. The first line of evidence comes from g, canadensis. Blister beetles are relatively sedentary and a large number of beetles can be found on the same clone over the flowering period of the clone. Correlations were calculated between the percentage of filled seeds per clone and blister beetle density (the maximum number of beetles recorded on a Figure 16: 74 Percentage of Filled Seeds for S, canadensis Clones Assigned to Different Maximum Flowering Dates (MFD) in 1980. Values are mean percentages with a 95% confidence interval indicated by bars. The means and confidence intervals are backtransformed following angular transformation. The Apia availability estimate is given for each date on which a visual census was conducted. The approximate date to peak bloom for the population is shown by the arrow. In this figure, S3 canadensis refers only to §, canadensis var. scabra. 7S AOV ADO—x.>._...:m<.:<>< 2&4 0 O 0 0 4 3 2 0 3 — l 2 . .9: v Kw ’ s _ / — 0' .I s o 7 m I. d m ./ o 3 m I. 5.. I. 0 o 3 O 0 6 4 m 0 26:33; 3:: to “9:23;. SEPT AUGI Figure 17: 76 Percentage of Filled Seeds for S, ggaminifolia Clones Assigned to Different Maximum Flowering Dates (MFD) in 1980. Values are mean percentages with a 952 confidence interval indicated by bars. The means and confidence intervals are backtransformed following angular transformation. The Apia availability estimate is given for each date on which a visual census was conducted. The approximate date of peak bloom for the population is shown by the arrow. 77 .9 80:3 >:§<:<>< ma< L o u .z m Illmv . m a m ’ m a m T1 0’. .5. F. It . w w m 0 $1383 3:: to 35235.. I7 13 28 AUCS 24 SEPT Figure 18: 78 Percentage of Filled Seeds for S. nemoralis Ramets Assigned to Different Maximum Flowering'Dates (MFD) in 1980. Values are mean percentages with a 95% confidence interval indicated by bars. The means and confidence intervals are backtransformed following angular transformation. The number of Apia collected per 50 inflorescences is given for each date. The approximate date of peak bloom for the population is shown by the arrow. 79 (0)813wva 09 Had SldV O N 2 2 n O nemoralis (H4) 30339 03111:! JO 39V1N3383d SEPTEMBER Figure 19: 80 Percentage of Filled Seeds for S, Quncea Ramets Assigned to Different Maximum Flowering Dates MFD in 1980. Values are mean percentages with a 9SZ confidence interval indicated by bars. The means and confidence intervals are backtransformed following angular transformation. The number of native bees collected per minute of sampling time is given for each date on which a census was conducted. 81 II. lil.fil— .8 322.2 5.. mum; m>: .05, Tukey's Tests) among the mean abundances of blister beetles per clone for clones in the B (0.10 i 0.11) (X -_¢-_ 952 CD, I (0.02 1 0.02), and L (0.07 i 0.08) phenology groups. Therefore, there is no reason to expect that blister beetles were an important factor determining the percentage of filled seeds over the flowering period of the population. One possible cause for this negative relationship is that blister beetles eat many disc stigmas, thereby reducing seed set per flower. Along with the stigmas, the beetles remove many anthers, and therefore much of the available pollen, from clones with large numbers of blister beetles. This could greatly reduce the desirability of these clones to pollinators foraging for pollen. Olsen (1975) found that honeybees collected approximately 82 of all their pollen from Solidago spp. in various sites in southwestern Michigan. After logarithmic transformation, there is in fact a significant negative correlation between the numbers of honeybees and blister beetles on clones of Solidago canadensis (r - -0.54, P < .01). No aggressive encounters between blister beetles and honeybees have ever been observed. There was a significant, negative correlation between blister 83 beetle abundance per clone and the percentage of filled seeds in -S_. ‘ggaminifolia (r - -0.41, P < .02). In the case of S, 55aminifolia, there was also a significantly (P < .01) greater density of blister beetles (the maximum number of beetles per clone divided by the number of ramets per clone) on early-flowering clones (0.13 i 0.06) (X I 952 CI) relative to late-flowering clones (0.02 i 0.02). Very few fl were recorded on early-flowering clones of S, ggaminifolia. But it is unlikely that the blister beetles were responsible for the lack of Apia early in the flowering season of S3 graminifolia because Apia were also not visiting early-flowering clones of g, canadensis var. canadensis which flowered synchronously with S, graminifolia and had almost no predation by blister beetles. Nevertheless, whatever the actual mechanism is by which Epicauta reduce seed set in goldenrods, it is not possible to attribute the low percentage of filled seeds in early“ flowering S3 graminifolia clones solely to the low frequency of honeybee visits. Solidago 122232 was first visited by blister beetles in mid-August. On the three dates for which census data are available, the number of blister beetles per ramet with at least 401 of all heads in flower increased from 1 beetle per 37 ramets (2.72) on 9 August, 1980 to 1 beetle per 9 ramets (112) on 13 August and 1 beetle per 5 ramets (201) on 18 August. It is therefore possible that at least some portion of the reduction in the percentage of filled seeds which occurred after 13 August, 1980 (Figure 19) can be attributed to predation by blister beetles. However, observations made between 23-28 August, 1980 indicated a decline in the abundance of blister beetles later in the season; it is likely that the low seed production very 84 late in the flowering season (the latest MFD was 26 August) of _S_. Juncea was mostly due to low visitation rates of pollinators. Solidago nemoralis was rarely visited by Epicauta and it is unlikely that flower predation had an effect on seed production. Overall, it appears as if the relative frequency of visits by honeybees over the flowering season had an effect on the percentage of filled seeds in S, canadensis, S, nemoralis, and possibly §3 graminifolia. Flower predation by blister beetles affects seed production in S, canadensis uniformly over the flowering season, but seems to cause differences in the seed production of early-, intermediate-, and late-flowering clones only in S3 graminifolia and possibly in S, Juncea. There is no evidence from data on insect visitors of pollinator limitation of seed production in S, juncea. For the other three species with adequate data to assess insect visitation rates over the flowering season, it appears as if changes in the frequency of visits by honeybees plays at least some role in determining seed production. Solidago juncea was never visited by Apia and this could possibly be the cause of the low overall seed production in this goldenrod. The Relationshipretween Goldenrods and the Plant Community Because it seems as if changes in the relative abundance of honeybees over the flowering season affect seed production of goldenrods, it is of interest to determine if the changes in the abundance of Apig on Solidago spp. can be related to the flowering phenologies of other species in the plant community which are visited by honeybees (cf. Table 2, Methods). Sweep samples and visual counts of insects visiting these species showed that they were all visited by _1 85 ‘épig_and native bees of the same species which visit goldenrods. Three of the six species (Trifolium repena, I, pratense, and Melilotua Slkfl) are considered to be major nectar and/or pollen plants for honeybees in the Midwest (Jaycox 1976). Honeybees began visiting Solidago app. when most of the introduced species had reached the end of their flowering periods (Figure 20). Solidago juncea flowered simultaneously with the introduced plants and was never visited by Apia. Ginsberg (1979) reported that in New York State S, juncea was visited heavily by épi_, However, there was great variability between years in his study; Apig accounted for 502 and 52 of the total number of honeybees and native bees collected from g, juncea in two consecutive years. Solidago juncea flowered earlier in the year with few visits by épig, Ginsberg's results showing that épig will visit S, Juncea suggest that there are no intrinsic reasons -- other than availability of more preferred sources of nectar and pollen -- why épig did not visit S, juncea at KBS in 1980. Solidago ‘ggaminifolia had a low abundance of Apia during the first half of its flowering season and this may be attributed to overlap with the flowering periods of introduced plant species. The introduced species did not show a consistent decline (from 20 August to 29 August) in the numbers of Apig on each species; it is therefore not possible to state with certainty that introduced species are competing with goldenrods for honeybee visits. The sweep samples which were taken to assess the relationship between honeybee visits to Solidago app. and the flowering phenology of the introduced plants may not be adequate because they were taken from small areas at nearby sites. Certainly the correlation between patterns of Apia abundance on Figure 20: 86 Flowering Phenologies of Four Goldenrods and Six of the Common Bee-Visited Plant Species in the Vicinity of the Study Site. The flowering phenologies of Solids o app. are reported as the percentage of clones (or ramets) with at least 102 of all heads in flower. The flowering phenologies of the other six species are reported as a percentage of the maximum number of inflorescences, etc. (see Table 2) counted for each species throughout the flowering season. The six species, which were all introduced from.Europe, are as follows: 1 - Centaurea maculosa (mowed); 2 - C. maculosa (unmowed); 3 - Melil otus alba (unmowed); 4 -’M. -alba (mowed); 5 - Arctium minus; 6 - Cirsium arvense; 7 - -Trifolium pratense; 8- T. repena. The vertical line and arrow indicate the first date on which a honeybee was observed visiting clones of S, canadensis and S, graminifolia. Psacenuos or CLONES wnu 210% PERCENTAGE OF MAXIMUM VALUE OE All. HEADS IN FlOWER 100 80 60 40 20 100 O O O O ‘ O N O O 87 Summer Flora 0—0 I ONO 2 0—0 3 0—0 4 o H 5 a—o 6 H 7 H 8 .\ . \ O l 1 Firs: Apis on Goldenrod Goldenrods A S. juncaa A S. graminifolia . S. canadensis O S. nemoralis I i 1 I T ‘ I 10 30 20 9 29 18 8 JUNEI JULY I AUGUST I sen Iocr 88 goldenrods and the flowering phenology of the introduced species deserves more attention. Seed Predation Except for S, nemoralis, seed predation by casebearer larvae was negligible (~ $_IZ). Seed losses per ramet in S, nemoralis averaged 5.42 of all seeds and ranged as high as 501 of all potential seeds. Seed losses were nearly significantly higher (P < .10) in the early- flowering ramets (7.52) than in the late-flowering ramets (3.52). There was, however, no correlation (r - 0.004, P >> .05) between the percentage of filled seeds per ramet and the percentage of seeds lost to predation. This suggests that the low percentage of filled seeds in the early-flowering ramets was not related to predation by casebearers. That this is indeed the case is supported by the fact that if the data are analyzed using only clones with little or no predation the mean percentages of filled seeds for the E, I, and L phenology groups are not different than when all clones are used. Experimental Crosses To this point, the results suggest that changes in seed production over time and differences in seed production among species may be related to differences in the relative abundances of pollinators and flower predators. However, it is possible that there are environmental effects or physiological differences among early-, intermediate-, and late-flowering clones which could account for changes in seed production independent of the frequency of insect visits. Experimental crosses performed on S, canadensis, _S_. juncea, and S, gaminifolia were designed to test this hypothesis. 89 Solidagg canadensis By comparing the OPEN CROSSES with the untreated clones it is possible to hold all factors constant except for the amount of pollination received by the ray stigmas. This comparison therefore tests for pollinator (or pollen) limitation of seed set versus physiological or environmental control of seed set. By comparing the BAG CROSSES to the OPEN CROSSES and the BAG CONTROLS it is possible to test the effectiveness of the crossing technique in the absence of pollinators. There are no significant differences between the OPEN CROSSES and the BAG CROSSES (Figure 21). Because the BAG CROSSES were never exposed to pollinators, this result demonstrates that the experimental crosses were effective. The greater percentage of filled seeds in the BAG CROSSES relative to the BAG CONTROLS is further evidence for the effectiveness of the experimental crosses. There was an increase in the percentage of filled seeds among the E, I, and L phenology groups for the control ramets with no experimental crosses (already described, Table 5) as well as in the OPEN CROSSES and the BAG CROSSES (Figure 21, 22, Table 8). For both the BAG CROSSES and the OPEN CROSSES, the early-flowering clones had significantly lower percentages of filled seeds than the late-flowering clones. The BAG CONTROL treatment also showed increases in the percentage of filled seeds from the E to the L phenology groups, but the differences are not significant (Figure 21). Furthermore, if differences in the percentage of filled seeds among the E, I, and L phenology groups are reanalyzed using the percentage of filled seeds for each clone minus the percentage of filled seeds in the BAG 90 AamV Aaav Away Asav Aan.m a o_.~v Amo.o_ u ms.mV Aeo.o u «2.2V Ano.o u m~.ov _o.m mas.e «ma.n am~.~ aoeazoo e mo wwnmfiacm wouua momma m.%oxaa ha flo. v e um acououuuv mHuamoquaawam one uuouuofi ucououuuv we vomoHHou so» zoom aw manor .aouuaauOMmaauu amasmao wauaoaaow coauoumaauuxoan coon o>an mHo>uouaa ooaovuuaoa .aaouw monoaona coma cw mommouo so“: mocoao mo muonaaa on» was mass: can mHo>uoucu ooaovaucoo Nmo sea was momosuaouma a“ ao=Ho> may wo mowwucouuoa some one eo=~a> aw mammouu Heuaoaquoaxm you ovoom voaaum uo owouaouuom .uvooo voadau .masouo mwoaoconm mum; can .oumqwoauouaw .hHaaw "uqaaovwaaa owavaaom um oases Figure 21: 91 Percentage of Filled Seeds from OPEN CROSSES, BAG CROSSES, and BAG CONTROLS from S. canadensis Clones in Different Phenology Groups. Values are mean percentages with 95% confidence intervals indicated by bars. The means and confidence intervals are backtransformed following angular transformation. PERCENTAGE OF FILLED SEEDS I00 G O 0 O 5 O N O 92 Solidago canadensis T BAG cnosses 1 OPEN crosses I no CONTROLS )7 ’ , I A I E I L ALL PHENOLOGY GROUP 93 Figure 22: Percentage of Filled Seeds from OPEN CROSSES and Untreated Clones of S. canadensis in Different Phenology Groups. Values are—bean percentages with 952 confidence intervals indicated by bars. Means and confidence intervals are backtransformed following angular transformation. 94 100 Solidago can nsis ‘9’: so 1 OPEN caosses 3‘, T Open. no crosses O I“ d A -'-‘ 60 II- II- o . III-l ‘ . ‘2 4° . .— Z I” U 35 a. 20 0 E l L ALL PHENOLOGY GROUP 9S CONTROLS, the conclusions originally presented in Table 5 are unchanged: early-flowering clones have significantly lower seed set per flower, whether hand pollinated or not. From a 2-way analysis of variance (cross treatment X phenology group), only the late-flowering clones (L) had a significantly higher percentage of filled seeds in the OPEN CROSSES (Bonferroni t-test, one-tailed, P < .05) relative to the untreated clones (Figure 22). However, the overall contrast between the OPEN CROSSES and the untreated clones was highly significant (Bonferroni t-test, two-tailed, P < .01). These results are interpreted to mean that g, canadensis clones were pollinator (or pollen) limited throughout the flowering season, and that the degree of limitation was greatest for the late- flowering clones. This result coupled with the parallel trend in percentage of filled seeds in the OPEN CROSSES and the untreated clones (Figure 22), suggests that the difference in the percentage of filled seeds between early- and late-flowering clones was not due to a difference in the relative abundance of insects, but rather to physiological or environmental differences among clones. Solidago graminifolia There were no significant differences between the BAG CROSSES and OPEN CROSSES (Figure 23, P > .05, Bonferroni t-tests), but there was a very low percentage of filled seeds in the BAG CROSSES for the L phenology group. Overall, both crossing treatments had a much higher percentage of filled seeds than the BAG CONTROLS. Solidago graminifolia had a significantly lower percentage of filled seeds in the late-flowering clones in both the OPEN CROSSES and the BAG CROSSES (Table 9). Overall, there was no significant 96 difference (P > .05, Bonferroni t-test) between OPEN CROSSES and untreated clones, but the OPEN CROSSES had a significantly greater percentage of filled seeds (P ( .01, Bonferrroni t-test) in the E phenology group relative to the untreated clones (Figure 26). There was no significant difference (P > .05) between the percentage of filled seeds in the OPEN CROSSES and the untreated clones in the L phenology group. The results of the experimental crosses suggests that the percentage of filled seeds in early-flowering §3 graminifolia clones is limited by low relative abundances of pollinators or by flower predators; late-flowering clones appear to be at maximum potential seed set per flower. Solidago luncea No BAG CROSSES were performed on g, luncea. The OPEN CROSSES in E3 juncea showed no significant differences in the percentage of filled seeds among phenology groups or between untreated ramets and OPEN CROSSES (Figure 25). These results suggest that the low percentage of filled seeds in g. Juncea (relative to the other goldenrods) was not the result of pollinator limitation; at least in 1980, g, Juncea appeared to have had a low maximum potential for seed production. The lack of a significant relationship among phenology groups in the OPEN CROSSES suggests that the reduction in the percentage of filled seeds from the E to the L phenology group was caused by a paucity of pollinators and/or an abundance of flower predators in the later phenology group. The absence of pollinator limitation of seed set 1“.§f juncea should not be taken as evidence that native bees and beetles are as effective as honeybees at pollinating goldenrods. Early-flowering 'w I. 97 clones of £3 graminifolia were visited by many beetles and native bees, but exhibited seed set limitation due to the amount of pollen reaching stigmatic surfaces. This suggests that native bees and beetles may not be as effective as honeybees at pollinating goldenrods, but the densities of the various insect species must be strictly controlled in order to draw any definite conclusion on this matter. 98 Table 9: Solidago graminifolia: Percentage of Filled Seeds for Experimental Crosses in Early, Intermediate, and Late Phenology Groups. Values are mean percentages of filled seeds. The values in parentheses are the 95% confidence intervals and the number of clones with crosses in each phenology group. Means and confidence intervals have been backtransformed following angular transformation. Means in each row followed by different letters are significantly different at P < .05 by Tukey's Tests after analysis of variance on angular transformed data. Treatment E L ALL Open, No cross 25.928 41.33b 34.47 (16) (21) (37) OPEN cnossss 50.3981 27.068 42.34 (31.82 - 68.90) (14.42 - 41.94) (28.83 - 56.46) (8) (4) (12) BAG CROSSES 62.358 4.06b 34.44 (39.24 - 82.82) (0.00 - 29.91) (10.14 - 64.29) (6) (4) (10) BAG CONTROL 4.578 1.228 2.61 (1.47 - 9.27) (0.02 - 5.48) (1.92 - 3.40) (3) (4) (7) 1 .05 < p < .10 99 Figure 23: Percentage of Filled Seeds from OPEN CROSSES, BAG CROSSES, and BAG CONTROLS from S. graminifolia Clones in Different Phenology Groups. Valfies are mean percentages with 95% confidence intervals indicated by bars. Means and confidence intervals are backtransformed following angular transformation. PERCENTAGE OF FILLED SEEDS 100 80 60 40 20 100 Solidago graminifolia 1 OPEN caossss TBAG caossss I BAG CONTROLS -_. E L PHENOLOGY GROUP ALL Figure 24: 101 Percentage of Filled Seeds from OPEN CROSSES and Untreated Clones of S. graminifolia in Different Phenology Groups. Values are—mean percentages with 95% confidence intervals indicated by bars. Means and confidence intervals are backtransformed following angular transformation. 102 m30¢0 >00._OZwIm .3< ._ m 0 ON hn. 0V Av 00 3303 OcéoaO m 1.. mumm0¢u meo H on 2.3.55.3 omega... oo— SOSSS OETIH :IO 39V1N3383d 103 Figure 25: Percentage of Filled Seeds from OPEN CROSSES, BAG CONTROLS, and Untreated Ramets of S, juncea in Different Phenology Groups. Values are mean percentages with 95% confidence intervals indicated by bars. Means and confidence intervals are backtransformed following angular transformation. The confidence interval for the BAG CONTROLS is too small to be represented in the figure (see the NO Cross data in Table 4). 104 .34. “.3010 >OO._OZmIn_ dog—.ZOU 046 G 3305 O: .coaOImoI mumm0¢u Zme H. 03:34. a O O O O V N $0338 031)” JO 39V1N33213d O O OO— CHAPTER 4 DISCUSSION A summary of the results is provided in Chapter 5. Factors Affecting Flowering Time within Natural Populations The highly significant, positive correlation between the relative phenology ranks of S, canadensis clones in 1979 and 1980 suggests that differences in flowering time among clones are determined either by genetic differences or by relatively-fixed microsite differences in the environment. This is further supported by data from S, graminifolia in which the latest-flowering clones in 1979 were among the latest- flowering clones in 1980. Primack (1980) found similar constancy of phenology ranking within three species of shrubs which had a great deal of individual variation in flowering time within populations; there were strong positive correlations between the flowering ranks of individual shrubs in different years. If it is true that plant populations are composed of individuals which exhibit great constancy in their relative phenology ranks in consecutive years, then it is likely that seasonal changes in the environment such as pollinator availability may have differential effects on plants which consistently flower early or late in the flowering season of a papulation. Assuming that flowering times are heritable, if differential seed set occurs over the flowering season, then flowering time may be subject to selection pressure from a number of factors (i.e. pollinators, predators) which can affect seed set over the course of the flowering season. There is no doubt that flowering phenology is subject to genetic control. A number of plant species show genetic differentiation in 105 106 flowering time between populations from different geographical locations (Hodgkinson and Quinn 1978; Somers and Grant 1981; Jones 1978; Murfet 1977) as well as from closely adjacent populations (McNeilly and Antonovics 1968). Within populations, the flowering times of individuals have been shown to be genetically controlled (Murfet 1977; McIntyre and Best 1978; McMillan and Pagel 1958) and flowering time has been shown to respond very rapidly to selection (e.g. Corn, Paterniani 1969). MdMillan and Pagel (1958) found genetically determined early- and late-flowering clones of Symphoricarpos occidentalis. The strong between-year correlations in phenology rank for goldenrods were likely to have been determined by genetic differences among clones. The evidence which supports this hypothesis is that goldenrod clones with very different flowering phenologies are often seen growing next to one another on level ground. There are no obvious environmental factors which could cause the marked differences in flowering time. On the other hand, microenvironmental conditions have been found to be very important factors controlling flowering phenology in a number of spring wild flowers (Jackson 1966). Solidago canadensis does seem to flower later in moist environments. When the flowering phenologies of ramets were recorded along transects through dense populations of S, canadensis at the top (dry) and bottom (wet) of a steep slope in an abandoned field near McKay Field, the ramets in the dry part of the slope flowered earlier and reached the past-flowering stage sooner than ramets in the wet areas. However, the degree to which the wet and dry ends of the slope appeared to differ in moisture content and density of vegetation, was much greater than any noticeable 107 microsite differences in McKay Field. In general, the environments in which the clones of all four goldenrods were growing in.McKay and Louden Fields were relatively homogeneous. Even though there was a more pronounced environmental gradient over the slope than there was in McKay Field, the delay in the flowering time of ramets in the wet area of the slope was less than a week. This delay does not account for the difference in flowering time between early- and late-flowering clones in McKay Field. Late-flowering clones began flowering and reached peak flowering approximately two weeks later than early-flowering clones. This suggests that genetic effects may have been most important in determining flowering time for goldenrod clones in McKay Field. However, the degree to which environmental and genetic factors determine flowering time in goldenrods should be investigated in more detail by transplanting ramets of different clones into controlled environments. Factors Limiting Seed Production ig_Goldenrods Physiology: All four species of Solidago exhibited differences in seed set for clones flowering at different times during the flowering season. Superficially, it appeared as if changes in pollinator abundance on Solidago clones could account for differences in seed set over the flowering season. If no experimental crosses had been performed, the data on seed set alone would suggest that the low percentage of filled seeds Of early-flowering clones of S, canadensis, §,'g£aminifolia, and g, nemoralis resulted from a low frequency of visitation by honeybees, the major pollinator of these goldenrods. In actuality, clones of S, canadensis were pollinator (or pollen) limited throughout the flowering season; this limitation appeared to be most 108 severe for the late-flowering clones. In addition, the percentage of filled seeds in the early-, intermediate-, and late-flowering clones was also subject to genetic or physiological limitation: when all.§, canadensis clones received adequate pollination in the experimental crosses, the late-flowering clones had the greatest capacity for seed production. Furthermore, only the lateflowering clones had significantly higher percentages of filled seeds in the experimental crosses relative to the untreated clones, suggesting that the late-flowering clones -- which had the highest percentages of filled seeds in the population - ‘were more vigorous than intermediate- and early-flowering clones. Although late-flowering clones of S, canadensis have larger inflorescences, they are not taller (121 i 19 cm) (X I 952 0.1.) than early-flowering clones (114 :;8 cm) and there is no correlation between clone height and the percentage of filled seeds (r - -0.017, P > .05) or clone height and inflorescence size (r - 0.182, P > .05). Neither is there a difference in clone size (ramets per clones) between early- and late-flowering S, canadensis clones (see p. 56). Solidago nemoralis also had no correlation between ramet height and the percentage of filled seeds (r - 0.098, P > .05); however there is a weak positive correlation between ramet height and inflorescence size (r - 0.419, P < .01). As with _S_. canadensis, late-flowering _S_. nemoralis clones had the largest inflorescences. Because there is no difference in ramet height between early- and late-flowering clones of S, canadensis, late-flowering clones -- by virtue of their larger inflorescences (Table 7) -- probably allocate a larger proportion of their total biomass to reproductive structures. 109 There is a very close relationship between total biomass and height of S, canadensis ramets (P. A. Werner, unpubl. data); therefore, ramets with similar heights are unlikely to have very different total biomass. Therefore, one may also conclude that early- and late-flowering clones of S, canadensis, and possibly S, nemoralis, do not differ so much in vigor as in the way in which biomass is allocated to growth versus reproduction. It is possible that, by taking longer to flower, late-flowering clones build up proportionately larger carbohydrate stores which facilitate the production of larger inflorescences and the filling out of larger proportions of the seed crop. As long as nitrogen levels are not extremely high (which is surely the case for goldenrod populations), stored carbohydrates make significant contributions to grain yield (Yoshida 1972) and it is very possible that late-flowering clones have larger carbohydrates stores to devote to reproduction. Although S, juncea and S, graminifolia did not exhibit correlations between inflorescence size and seed set over time (see Tables 5 and 7), both species had the greatest percentage of filled seeds in the OPEN CROSSES for the phenology groups with the largest inflorescences (See Table 7, Figures 24 and 25). Even though there were no significant differences among phenology groups in the S, juncea crosses and between S, graminifolia seed volumes in the two phenology groups, the fact that the general pattern is comparable to that in S, canadensis (Table 7, Figure 21) suggests that the relationship between potential seed production per flower and inflorescence size should be investigated in greater detail in Solidago spp. Although no experimental crosses were performed on S, nemoralis, 110 seed production per flower increased with inflorescence size (see Tables 5 and 7). Schemske (1980a) and Stephenson (1979) found that fruit set per flower increased with inflorescence size. This was the case with _S_. canadensis (Figure 26) and with S, nemoralis (see Tables 5 and 7). Larger inflorescences had greater seed set per flower as well as greater numbers of seeds per inflorescence. In contrast, Willson et al. (1979) and Schemske (1977) found that inflorescence size (number of flowers) was positively correlated with total seed set per inflorescence, but not with seed set per flower. Lloyd and Primack (1980) and Barrett (1980) found no correlation between flower number and fruit set per flower in a number of plant species. Greater total seed set in larger inflorescences relative to smaller inflorescences may result from the greater attractiveness to pollinators of larger inflorescences. But, the experimental crosses which demonstrated greater capacity for seed set per flower in larger inflorescences suggest that in goldenrods larger inflorescences may be associated with a greater physiological capacity for seed production. Regardless of the mechanism, the seed set of goldenrods was subject to limitation at different levels throughout the flowering season. Other studies have found that seed set may be limited by resources or physiological capacity (Willson and Rathcke 1974; Willson and Price 1977; Schemske 1977; Schemske et al. 1978; Stephenson 1979; Lloyd 1980; Dafni and Negbi 1980) and by pollinator availability (Schemske 1977; Waser 1979; Barrett 1980; Bierzychudek 1980; Willson and Schemske 1980; Schemske 1980a; Melampy and Hayworth 1980; Zimmerman 1980a). 111 Figure 26: Volume of Seeds per Inflorescence and Percentage Of Filled Seeds per Clone for S, canadensis Clones in Different Phenology Groups. Values are means and the 95% confidence intervals for seed volumes are indicated by bars. Percentages of filled seeds are backtransformed means following angular transformation. 45 205 Sofidago canadenfis 180 112 I (0) $0339 0311” :10 39V1N3383d n N .— In I 1 40 O O O O 0 N (0) $0339. :10 ameA PHE NOLOGY GROUP 113 Intraclonal pollinator movements also appear to be an important factor limiting seed set in several plant species. In several self- incompatible plant species, seed set seems to be limited by a large proportion of geitonogamous (intra-plant) pollinations resulting from pollinators remaining at a single plant which provides abundant nectar rewards (Schemske 1980b; Carpenter 1976; Frankie et al. 1976). However, in goldenrods, both S, canadensis and S, graminifolia clones showed no correlation between the percentage of filled seeds and the number of ramets per clone (S, canadensis: r - 0.092, n - 53, P > .05; ‘S. graminifolia: r - -0.256, n - 36, P > .05). A significant negative correlation would have suggested that seed set was lowered due to pollinators remaining in large clones for long periods of time. For all S, canadensis clones, there was a weak but statistically significant negative correlation (r - -0.274, n - 53, P < .05) between the percentage of filled seeds and the distance to the nearest neighbor of similar flowering stage (i.e. plants in bud were not assigned nearest neighbors which were almost past flowering, Figure 27). Silander (1978) has also reported a negative correlation between seed set and nearest neighbor distance in the self-incompatible legume, Cassia biflora. However, there were no significant differences among the nearest neighbor distances of early- (3.0 i 1.7m) (X i 952 0.1.), intermediate- (3.6 1- 1.1m), and late-flowering (3.4 i 1.7m) clones of S, canadensis. This suggests that density dependent effects on seed set are not likely to account for the differential seed set over the flowering season, at least for S, canadensis. Pollinators and/or flower predators were especially important in reducing seed set of early-flowering S, ggaminifolia clones. The Figure 27: 114 Relationship Between Percentage of Filled Seeds and Distance to Nearest Neighbor for S. canadensis Clones. Percentages of filled seeds have'EOt been subjected to any transformations. Clones were assigned nearest neighbors of similar flowering stage (i.e. a clone in bud stage was not assigned a nearest neighbor which was nearly past flowering). There is a weak negative correlation between the variables (r - -0.274, n - 53, p < .05). PERCENTAGE OF FILLED SEEDS 115 i canadensis 2 4 6 8 IO DISTANCE TO NEAREST NEIGHBOR (m) 12 116 average density of blister beetles per ramet in the early-flowering clones was 0.133 1: 0.062 (X i 952 C.I.) (1 per 7.5 stems). Relative to the average seed set of clones with no blister beetles (Figure 28), this density of blister beetles corresponds to approximately a 30% reduction in seed set. Therefore, it appears as if approximately 702 of the difference between the seed set of untreated clones and OPEN CROSSES (Table 9, Figure 24) can be attributed to pollinator limitation in early-flowering clones. From the experimental crosses (Table 9, Figure 24), late-flowering clones of S, graminifolia appear to be at maximum potential seed set. During the latter half of the flowering season, the average density of blister beetles was low (0.021 1 0.016) (1 per 48 stems) and the density of honeybees was high (Figure 17). Therefore, it is unlikely that flower predation caused much reduction in seed set, at the time when pollination was probably most effective. Seed set in S, canadensis was limited by pollinators (or pollen) throughout the entire flowering period. Because the physiological potential for seed production increased along with the frequency of honeybee visits (Figure 16 and Figure 21), the degree to which pollinators limited seed set remained fairly constant over the flowering season. The drop in honeybee abundance on S, canadensis clones late in the flowering season (Figure 16) may account for the fact that pollinator- limitation was most severe for the late-flowering clones. If honeybees remained at the level of abundance that they had reached early in the flowering season (see Figure 16), then seed set probably would have been more pollinator limited for intermediate- and late-flowering clones. Alternatively, if honeybees became abundant 117 earlier in the flowering season, then early-flowering clones probably would have reached physiological maximum levels of seed set. Because there were no significant differences among the densities of blister beetles in the E, I, and L phenology groups (see p. 82), it is unlikely that the changes in honeybee densities over the flowering season could have resulted from interactions with blister beetles. Even though blister beetle densities over time suggest that these I insects do not cause markedly different reductions in seed set at different times during the flowering season, blister beetles may cause 4 a relatively constant reduction in seed set over time. Blister beetles may limit seed set directly by eating stigmas as well as indirectly by eating pollen (thereby making clones less attractive to honeybees, or perhaps causing pollen limitation pg: gg_in the population). Because blister beetles do appear to reduce seed set in goldenrods, the presence of blister beetles over the flowering season of S, canadensis suggests that some percentage Of the difference between the observed and maximum potential seed set of S, canadensis (Figure 22) is due to flower predation by blister beetles. The average densities of blister beetles per stem in the E, I, and L phenology groups were 0.0979 (1 per 10 stems), 0.0228 (1 per 43 stems), and 0.0674 (1 per 15 stems), respectively. Relative to the average seed set of clones with no blister beetles (Figure 29), these densities of beetles correspond to approximately 172, 62, and 122 reductions in seed set. These estimates can be checked by comparing the mean percentage of filled seeds in the E, I, and L phenology groups which include all S, canadensis clones (Table 5) to the mean percentage of filled seeds in the three phenology groups when only clones which 118 were not visited by blister beetles were used to calculate means. The percentage of filled seeds in the phenology groups with blister beetles was always lower than the percentage of filled seeds in the same groups after clones which were visited by blister beetles were removed from the analysis (Table 10). In this case, the reductions in seed set due to blister beetles are estimated to be 232, 72, and 152 for the E, I, and L phenology groups, respectively. It is important to note that there are still differences among the mean percentages of filled seeds for the phenology groups which contain only clones which were not visited by blister beetles. Therefore, blister beetles did not cause the differences in seed set over the flowering season. If pollen limitation can reduce seed set in goldenrods, then it is possible that soldier beetles (Chauliognathus) may limit seed set early in the flowering seasons of S, canadensis and S, graminifolia. Soldier beetles eat much of the pollen from goldenrod clones (although they do not destroy stigmas as blister beetles do), and they probably do not transfer much pollen relative to honeybees and native bees. The high densities of blister beetles and soldier beetles on early-flowering clones of S, graminifolia and S, canadensis (Figures 8 and 10) may reduce the amount of pollen that is available for polliantion, thereby causing pollen limitation of seed set. This suggests a prediction that can be tested: pollinators (honeybees and native bees) should have smaller amounts of pollen on their bodies early in the flowering season if beetles are causing pollen limitation of seed set. It is important to note that pollinators, flower predators, and physiological factors limit seed set in S, canadensis and the effects of these factors mist be considered simltaneously. Schemske (1977) Figure 28: 119 Relationship Between Percentage of Filled Seeds and Density of Epicauta (Blister Beetles) for S. graminifolia Clones in 1980. Percentages have not been sEbjected to any transformations. Epicauta density is the maximum number of beetles recorded per clone divided by the number of ramets per clone. The arrows refer to the mean density of Epicauta per stem for clones in the E, and L phenology groups. The linear regression equation is Y - -76.88x + 40.55 (r - -0.413, P < .02). Mean percentage of filled seeds for clones with no Epicauta is 39.02. 120 o o o .m nm N o .m o w o o o r o o . c o s_ C mammm 03...... m0 m0os mHo>uOuCu oocovaucoo was scoot .mvooo moaaau mo nomsucoouom some who mosas> come no; aoqucouom o;u aouu new moon voosvou co«umu«a«~ uOumcuaaom was dunno“ u noun: an owoucoouom sumauxounnm ugh sum; was .oumuvoau0ucu .afiuom cw cacao you ovoom voaaum no owOucoouom .ouoo coEOOumcsuu uufiswco co moccauo> mo mammancs usuuo momma m.%oxsh AA no. v m um acou0uuuv huucooamucmuo one .=O«umahOuo=ouu madame: mausoHaom .msouw mwOHocosa some cu mucosa mo gonads ago was oas>uoucu oocovuucoo «no osu one oomozucoumm a“ uo=Hs> one .moouw mwOHococm sumo how commaao so .Aooucm>mwwccom suauuwmuv moauoom nouuaun ma vouwmq> uoz one: sown: mocoao mace mean: was muscuu HH< magma museum mmOHocofin ”muncovocmo .m «om manna 124 found that seed set per flower in Claytonia virginica was limited by pollinator availability both early and late in the flowering season. However, late-opening flowers suffered additional physiological limitation of seed set due to reduced photosynthesis after closure of the forest canopy. The degree to which pollinators, predators, and physiological factors (nutrient availability) may simultaneously affect seed set in species can only be detected if experimental crosses or determinations Of the frequency of ovule abortion are made throughout the flowering season. If experimental crosses are performed only at one point during the flowering season, erroneous conclusions could be reached. For example, given only the experimental crosses on the late-flowering S, canadensis clones, the most logical conclusion would be that early-flowering clones were severely pollinator-limited while late-flowering clones were only slightly pollinator-limited. Given only the experimental crosses on the early-flowering clones, the conclusion would be that late-flowering clones were not pollinator limited at all. The results Of experimental crosses performed over the entire flowering season show that neither of these conclusions is correct; seed set was limited to approximately the same degree throughout the flowering season (Figure 22). Pollinator limitation accounted for most of the limitation of seed set at any point during the flowering season (Table 11). Implications for £23_S£232.2£_Competition for Pollinators It has frequently been noted that co-occurring plant species which could utilize the same pollinators tend to flower at different times (e.g. Opler et al. 1975). Numerous authors have suggested that co- occurring plant species exhibit displaced flowering times as a .mosoao mounouuss on» was mummomu zumo may on swoon moaawm no owoucoouom onu coozuon oomououuwv unusumnmwun o: not upon» uo;u mcooa No mo you moon on couuosoou voumauuno :< u uom moon museums no no no no 33:38 new 83263 AA< A H N moons" annoudom mom no on. on. / \ .uom moon Elana! no no III non Honooouoo noun conuoooum mm« A H m unauomacwamwm owuvunom a m moo .E goo so ooo .E mom o... oo. o_. oo. n_. oo. oo. no. n_. / \ / \ / \ \ you coon 82:qu non non n2 non $353.. so: 52263— 444 A H N OfiDCOVflCflU OMQVfiflom .ouOuucuaaoa one mucumooun uoaouu Ou vopuuomm mcouuuomoum Oucu muscuuuuumm was gonna mowoucoouom um couponou Ono uom moon Houucouoa Boom acouuoavom .Amaumuov uOu uxOu oonv moauoon usumnan mo sunmcov msmuo> uom moon mo occummouwou aouu vocaELOuov onus you moon nonucOuon souu OCOnuoavou ovuuonon HH< .co«uou«a«4 Ammv uOuovonm was Agony uOumcnfiaom Oucw muscuuuuumm you move aaawxmz Houucouom Souk macuuoavou nu“ wanna 125 consequence of selection which reduces interspecific competition for pollinators (Robertson 1895; Croat 1969; Mosquin 1971; Frankie et al. 1974; Gentry 1974; Pojar 1974; Frankie 1975; Heinrich 1975, 1976b; Heithaus et al. 1975; Stiles 1975, 1977; Reader 1975; Feinsinger 1976; Carpenter 1976; Waser 1978a; Anderson and Schelfhout 1980; Pleasants 1980). This hypothesis has received support from theoretical studies which have shown that competition for pollinators may exclude a species from a plant community (Levin and Anderson 1970; Straw 1972; Bobisud and Neuhaus 1975; Waser 1978b). However, character displacement in flowering phenology provides only inferential, and therefore inadequate, evidence for the importance of present competition for pollinators to individual fitness and patterns of species distribution and abundance (Waser 1978a; Reader 1975; Brown and Rodric-Brown 1979; Rabinowitz et al. 1981). Indeed the existence of displaced flowering times has been challenged on the grounds that the community-level patterns of flowering times do not differ from random patterns (Poole and Rathcke 1979; Rabinowitz et al. 1981). These studies (e.g. Rabinowitz et al. 1980) have not necessarily utilized groups of species which are very likely to be competing for pollinators, and therefore, a random pattern is not unexpected. Furthermore, different methods of determining random community-level flowering patterns have yielded different conclusions (random versus nonrandom) about the observed flowering pattern in a single community (Pleasants 1980). Nervertheless, the valid point that these authors make is that patterns do not demonstrate the existence (or nonexistence) of processes. Competition for pollinators embodies two distinct mechanisms: 126 differential pollinator attraction and interspecific pollen transfer (waser 1978a,b; Reader 1975). Differential pollinator attraction occurs when one or more plant species draws pollinators away from co- occurring species which would otherwise be visited by the pollinators. This phenomenon has been demonstrated in a number of agricultural crops (Free 1968, 1970; Pedersen 1953) and in natural, albeit sometimes disturbed, plant communities (Mosquin 1971; Zimmerman 1980a). Haser (1978a) suggests that differential pollinator attraction will be most important in disturbed communities where plant and pollinator densities have not equilibrated. Interspecific pollen transfer, due to low pollinator constancy, results in wastage of pollen, reduction of stigmatic area available for suitable pollen, and reduction of the total number of effective pollinator visits. Waser (1978a) provides strong evidence for seed set reduction resulting from interspecific pollinator movements on Delphinium nelsoni and Ipomopsis aggregata. To provide evidence for current competition for pollinators it must be shown that (1) a plant species requires a pollinator to achieve maximum seed set, (2) a plant species suffers a reduction in seed set as a result of sharing one or more pollinators (or potential pollinators) with one or more co-occurring plant species (or with conspecifics if intraspecific competition is being investigated), and (3) if any reduction in seed set occurs in the presence of a potential competitor it is a result of fewer total number of visits by pollinators and/or reduced effectiveness of pollinator visits due to interspecific pollen transfer. If (3) is not shown then it is possible that reductions in seed set could be the result of physiological changes over the course of the flowering season, or perhaps increases 127 in herbivory on leaves or flower parts. Physiological causes for changes in seed set over time could be ruled out by performing experimental crosses throughout the flowering season. If seed set remains constant over the season in the crosses, then differences in seed set among plants in natural populations may be ascribed to the amount of effective pollen reaching the stigmas. In goldenrods, interspecific pollen transfer does not appear to be an important factor limiting seed set. Honeybees tend to be constant to individual species of Solidago (Ginsberg 1979), and in contrast to co-occurring plant species exposed to interspecific pollen transfer (Waser 1978), co-occurring species of goldenrod (S, canadensis, S, graminifolia) do not exhibit mutual reductions in seed set when blooming synchronously (compare Figures 16 and 17). Any competition for pollinators appears to result from differential pollinator attraction because all four species of Solidago require pollinators to achieve maximum potential seed set. However, the relative importance of pollinator versus physiological limitation of seed set varies among species. Although seed set in S, juncea was very low relative to the other goldenrods, the experimental crosses suggested that seed set was not limited by pollinator visits. Therefore, the low seed set was not the result of competition for pollinators. However, if the experimental crosses on S, juncea had provided evidence for pollinator limitation of seed set, then this goldenrod would provide an excellent example of the processes which could lead to competition for pollinators in natural plant communities. Solidago juncea flowered simultaneously with a group of introduced 128 plant species which attracted honeybees (Figure 20). Because honeybees are the major visitors to the other goldenrods, and S, juncea is visited by honeybees in other geographical areas (Ginsberg 1979), it appears as if the complete absence Of honeybee visits to S, juncea was caused by differential pollinator attraction. Many of the species which flowered simultaneously with S, juncea are important nectar and pollen sources for honeybees (Jaycox 1976; Olsen 1975), and as is the case with many introduced flowering plants, they were very attractive to pollinators due to their great abundance, long flowering periods, and abundant nectar (Heinrich 1975, 1976b). Furthermore most of the species of native bees which pollinate S, juncea were also abundant visitors to the introduced plant species. If seed set in S, juncea was not limited by physiological factors, the great reduction in potential visits by pollinators caused by differential pollinator attraction would possibly result in pollinator limitation of seed set in _S_. juncea. In any event, this provides a good example of the mechanisms by which seed set could be limited by competition for pollinators. There is some evidence that competition for pollinators may be affecting seed set in S, graminifolia and S, canadensis. The early- flowering clones of S, graminifolia flowered synchronously with several introduced plant species (Figure 20). Honeybees did not visit S, ‘graminifolia until 28 August, 1980 (there were no honeybees visiting S. graminifolia on 27 August) at which time S, graminifolia had almost reached the peak of the blooming season. It is likely that the lack of visits by honeybees was due to differential pollinator attraction between S, graminifolia and the introduced plant species. In untreated, early-flowering S, graminifolia clones, seed set was much 129 lower than potential seed set (OPEN CROSSES) (Table 9) and it is likely that the low frequency of honeybee visits accounted for the bulk of the limitation (approximately 702) of seed set. It therefore appears as if competition for pollinators plays a role in limiting the seed set of early-flowering S, graminifolia clones. Flower predators (Epicauta, blister beetles) also limit seed set in early-flowering clones of S, graminifolia (302 average reduction from potential seed set.). Only late-flowering clones of S, canadensis had significantly lower seed set relative to the experimentally crossed clones (OPEN CROSSES) (Figure 22); that is, pollinator (or pollen) limitation was most severe late in the flowering season. This appears to be due to a drop in the abundance of honeybees per Open capitulum late in the flowering period (Figure 16). Because late-flowering clones had very high potential seed set, the drop in honeybee abundance may have caused pollinator limitation of seed set. In McKay Field, Sg£g£_pilosus populations reached peak bloom on approximately 22 September, 1980. The number of honeybees per sweep sample decreased from 19 September to 23 September for S, canadensis and increased over the same period for S, pilosus (Figure 30). This suggests that honeybees were switching from S. canadensis to _A_. pilosus late in the flowering season of S. canadensis. However, without an appropriate control for density of S, canadensis, an alternate explanation is that honeybees were leaving _S_. canadensis simply because there were few clones in flower and not because 5, pilosus was a more attractive plant. If honeybees left late-flowering S, canadensis clones because of differential pollinator attraction, then it appears as if late-flowering clones suffered pollinator-limitation of seed set due to competition for pollinators. 130 Figure 30: Total Numbers of Apis Collected in Sweep-Sample Censuses of Solidago canadensis and Aster pilosus in McKay Field, 1980. NUMBER APIS PER 10 SWEEPS 50 A O o: O N O 8 131 Total Apis .z‘b‘. I ‘- o \. .1” ‘A .z ,z ,I O S. canadensis j A. 'I m osus 1 . IO 14 18 22 26 SEPTEMBER 132 One piece of evidence which suggests that honeybees were differentially attracted to _A_. pilosus comes from honeybee behavior as _S_. jgraminifolia: on that species, the number of honeybees per flower does not decrease late in its flowering season (Figure 17) and so low abundance of clones BEE gs does not ellicit a decrease in honeybee densities. Perhaps the most important implication of the present study for the study of competition for pollinators is that the level at which seed set is limited by physiological or environmental factors may be very different at different points during the flowering season. This requires that some measure of physiologiCal limitation of seed set be obtained throughout the entire flowering season. Aside from the present study, only Barrett (1980) has performed experimental crosses throughout the entire flowering season of a plant species to test for pollen limitation of seed set. Combinations of data on experimental crosses and rates of ovule abortion over the flowering season have also been used to produce reasonable estimates of the relative importance of pollinator and physiological limitation of seed set (Schemske 1977, Schemske et al. 1978; Melampy and Hayworth 1980). However, data on seed set per flower (Haas 1966; Hawkins 1966; Woodell et al. 1977; Zimmerman 1980a) or per clone (Primack 1980) over the flowering season are difficult to interpret in the absence of data which estimate levels of physiological limitations on seed set over the entire flowering season. For example, Zimmerman (1980a) has shown, that over a period of approximately 40 days, greater seed set in early-opening flowers on individual plants of Polemonium foliosissimum was correlated with 133 greater pollinator availability for early- relative to late-Opening flowers. Furthermore, experimental crosses performed on late-opening flowers demonstrated that seed set was pollinator limited during the latter part of the flowering season. The seed set from these crosses was not significantly greater than that of early-Opening flowers leading Zimmerman (1980a) to conclude that pollinators were not limiting seed set early in the flowering season. However, in the present study, the highest seed set in S, canadensis clones was correlated with the greatest insect availability, but these clones were still pollinator-limited. Crosses performed earlier in the flowering season and then compared to the natural seed set of later-flowering clones would have suggested that seed set was not pollinator limited at all in late-flowering clones. Also, Stephenson (1979) found that successive pollinations within inflorescences of Catalpa speciosa had successively lower probabilities of setting fruit. It is therefore possible that late-Opening flowers within a plant may have lower capacities for seed production then early-Opening flowers. These two situations are somewhat analogous to that in Zimmerman's (1980a) study and suggest that only with great caution should seed set from crosses performed at one point in the flowering season be used to estimate the degree of pollinator limitation in another part Of the flowering season. A second important implication is that pollinators are not the only factors which affect seed set over the course of the flowering season. Studies have shown that seed predation (Zimmerman 1980b), abiotic conditions (Hoodell et al. 1976; Schemske 1977; Schemske et a1. 1978; Dafni and Negbi 1980), and spatial densities of plants and 134 flowers (Carpenter 1976; Augspurger 1980) are also important factors affecting seed set at different times during the flowering season. Zimmerman (1980b) found that plants of Polemonium foliosissimum.which had the greatest seed set per flower also had the greatest percentage Of ovaries preyed upon per plant. This was not the case with S, nemoralis, the only goldenrod with significant pre-dispersal seed predation in the year of this study. Solidago nemoralis has the greatest amount of seed predation on early-flowering clones with the lowest seed set, thereby exacerbating the difference in total seed set between early and late-flowering clones. In S, graminifolia, flower predators (as well as pollinators) limited seed set in early-flowering clones. These results suggest that a number of factors must be studied in conjunction with pollinator availability to determine which factors are most important in limiting seed set over the course of a flowering season. Implications for £13: Evolution 2; Flowering _T_i_me;_ :92 the Structure 93 Plant Communities It is worthwhile to point out that there is a great deal of difference between attempting to document the processes which can select for changes in flowering time - which is the purpose of this study - and attempting to explain the factors which produced an observed pattern of flowering phenologies in a plant community. With respect to the four species of Solidago in this study, there are a number of factors which make it difficult to explain how the current pattern of flowering phenologies among the four species may have evolved. First, it must be recognized that, at least in the current study, the major pollinator (Apia) of goldenrods, as well as, the plant 135 species with which goldenrods competed for pollinators were introduced from Europe. Aside from the fact that goldenrods and honeybees did not have an extensive period of time in which to coevolve (perhaps 200 years), the relative abundances of native and introduced pollinators on goldenrods at different times of the flowering season appear to be largely determined by the flowering phenology of the introduced plant species. It is therefore impossible to determine what the temporal patterns of pollinator visits would be like if the goldenrods were exposed only to a comnunity of native plants. Although the four species of Solidago probably co-occurred in native prairie communities, the current data on pollinator abundances and temporal patterns of pollinator visits do not provide great insight into the conditions under which the current flowering phenologies of the four species of Solidago evolved. A second factor which must be considered is that the current distribution pattern of Solidago is very definitely associated with disturbed land. Therefore, it is not clear to what extent the current abundances of Solidago spp. reflect presettlement conditions -- it is likely that current abundances of Solidago spp. are much greater than in the past -- and to what extent a change in the abundance of goldenrod is associated with changes in the foraging activities of pollinators. Lastly, it is important to note that factors other than pollination may influence flowering time. For example, Solidago juncea flowers very early and perhaps this is correlated with the fact that S, juncea is the only one of the four goldenrods which has a prolonged period of vegetative growth as a rosette. It is possible that some aspect of the physiology of rosette growth (which may reflect selection for competitive ability during the stage of vegetative growth) selects 136 for early flowering individuals. Because it is not possible to draw very many conclusions concerning the factors which produced the current sequence of flowering in these goldenrods, the discussion will center on goldenrods as a model system which can be used to understand the processes which may select for flowering time in natural plant commnities. If effective arguments are to be constructed concerning the evolution of flowering time, then it is necessary to document that individuals exhibit differential seed set as a function of their flowering time within the flowering period of the population, Yet, there are very few studies which demonstrate that individuals which flower at different times in a population have differential reproductive success. While it is true that several studies have shown that flowers opened at different points during the flowering season of a population exhibit differential seed set (Carpenter 1976; Schemske 1977; Schemske et al. 1978; Waser 1978a; Woodell et al. 1977; Melampy and Hayworth 1979; Zimmerman 1980a,b; Barrett 1980), few studies specifically attempt to measure seed set for individual plants which flower at different points over the flowering season (exceptions are Primack 1980; Waser 1979; Augspurger 1978, cited in Augspurger 1980). For example, Zimmerman (1980a) showed that portions of plants whose flowers were opened during a pre-competitive phase of pollinator abundance had higher seed set than portions of plants whose flowers were opened during a competitive phase of the flowering season with a much lower ratio of bees to flowers. We can only surmise that some individuals had the bulk of their flowers opened in the precompetitive phase while others flowered mostly in the competitive phase. Likewise, 137 Waser (1978a) has shown that flowers of Delphinium nelsoni and Ipomopsis aggregata suffer seed set reductions due to interspecific pollen transfer at times when these species flower simultaneously. However, it is not clear if the flowers which overlap in blooming time belong to many plants with few flowers or few plants with many flowers. This distinction is critical for understanding reductions in the total seed set of individual plants exposed to potential competitors. The present study has shown that Solidago clones which flowered at different times during the flowering season had differential seed set on a per flower and a per individual basis. An interesting aspect of this result was that, at least for clones of _S_. graminifolia and _S_. canadensis (and ramets of S, juncea), peak seed set did not occur at the peak of the flowering season (i.e. when most clones or ramets were in flower), thereby suggesting that directional selection may be occurring for later (S, ggaminifolia, S, canadensis) or earlier (S, juncea) flowering. Other studies have also found that the time at which seed set was greatest did not correspond to the peak of the flowering season (Schemske et al. 1978; Primack 1980). Even if flowering time is genetically controlled, it is not necessarily true that these differences in seed set will result in evolutionary changes in flowering phenology. Primack (1980) lists three factors which could maintain large amounts of variation among the flowering times of individuals within populations. The first factor (Primack 1980) is that yearly variations in weather may result in between-year differences in the success of early- and late-flowering plants. This was not the case in S, canadensis. Despite a large between-year difference in flowering time 138 (late-flowering clones reached maximum flowering 7-10 days earlier in 1979 than in 1980), late-flowering clones were most successful and early-flowering clones were least successful in both 1979 and 1980 (Table 5) and the individual clones maintained their phenology rankings. Furthermore, there was a positive correlation (r - 0.78, p < .001) between the percentage of filled seeds per clone between years (1979 and 1980). This is in contrast to Rust and Roth (1981) who found that fruit and seed production was very variable among clones of Podgphylum peltatum in different years. Second, there may be selection for flowering time due to greater pollen dispersal late and early in the flowering season when there are low densities of flowering plants; the seeds from these crosses may have greater fitness than seeds from peak flowering time due to heterosis. Solidago canadensis clones did not exhibit different nearest neighbor distances among the three phenology groups; however, the clones in flower at peak bloom for the population had more flowering neighbors. Honeybees tended to move mainly between adjacent clones; therefore, as is usually the case (Levin 1974), most crosses probably occurred between nearest neighbors. If adjacent clones are not all closely related it is possible that intermediate-flowering clones may not be at a great disadvantage with respect to this factor. Third, yearly variations in flower and seed predators and fruit dispersers may result in varying selection pressures on flowering time, especially if fruit maturation time is correlated with flowering time. Flower predation by blister beetles (Epicauta) is unlikely to shift from early to late in the flowering season of the goldenrods. Blister beetle density peaked at the same time as soldier beetle 139 (Chauliognathus) density on S, canadensis and S, graminifolia; this occurred in late-August -early-September (Figures 11 and 13). Ginsberg (1979), working in New York, found that Chaulioggathus peaked in mid-August in both 1974 and 1975. These patterns suggest that it is unlikely that the peak in beetle densities would shift drastically between years. In S, canadensis the seeds are wind dispersed at the time of first frost in late autumn through early winter. Germination does not occur until early-summer of the following year. Although seeds of late-flowering clones did mature approximately 10-14 days later than early-flowering clones, there are no obvious reasons to expect that this two week difference in maturation time would result in differential success for seeds of early- versus late-flowering clones. Another possible mechanism for maintaining variability in flowering time within populations is if growth rate is correlated with flowering time. There were no differences in the heights of S, canadensis clones which flowered at different times during the flowering season; however, early-flowering clones reached their final height earlier than late flowering-clones. If seedlings and rosettes of early-flowering goldenrod clones have faster growth rates and allocate more biomass to vegetative structures early in the season, then it is possible that offspring of early-flowering clones may be better competitors during the early period of vegetative growth. If this were the case, then early-flowering clones may have an advantage at the seedling and early growth stage which offsets the disadvantage of producing fewer seeds relative to later-flowering clones. This last point raises the question of whether the number of seeds produced per clone is an adequate measure of individual reproductive 140 success. Certainly the contribution to the next generation made by the male function is also an important factor (Willson and Price 1977; Willson and Rathcke 1974), but almost every study which investigates the effect of flowering phenology on reproductive success uses seed production per flower or per plant as an estimate of reproductive success. A very important extension which needs to be made in the study of the evolution of flowering time is to begin investigating the portion of the genetic contribution to the next generation by an individual which is accounted for by seeds versus pollen. If there are different probabilities of successful establishment for individual offspring of plants with different flowering times it is possible that there will not be a one to one relationship between seed production and the probability of leaving offspring. This could be investigated in goldenrods by planting seeds from early-, intermediate-, and late- flowering clones under experimental conditions which test for differences in growth rates and survivorship. Furthermore, if there is a tradeoff between seed number and weight within a population (i.e. clones with high seed set have the lightest seeds) then (given that seed size is positively correlated with establishment success) it would be possible to have different probabilities of successful establishment for seeds of different clones; the clones with the lower seed sets would have higher probabilities of establishing offspring on a per seed basis. However, on an individual plant basis, it is necessary to determine if plants which produce more, light seeds leave the same or a different number of offspring relative to plants which produce fewer, heavier seeds. Because a number of studies have shown that seed size is positively 141 correlated with seedling success (see references in Harper 1977) a relationship between seed set and seed size would be very important if it existed. There is, however, no evidence that this is an important factor affecting the S, canadensis clones in the present study: the seed weights (fresh weights of filled seeds) of early- (82.3 2:14.211g) (X I 952 C.I.), intermediate- (89.5 i 7.0 pg), and late-flowering clones (75'7.:.11'7 ug) are not significantly different (P < .05). Along with factors affecting seed set per flower on a yearly basis, the total reproductive output of a goldenrod clone depends on its longevity and its potential for growth. If there is a tradeoff between seed production and clonal growth, then it is possible that early-flowering goldenrod clones may grow larger than late-flowering clones. Likewise, if there is a tradeoff between seed production and survivorship, it is possible that early-flowering clones may be longer* lived that late-flowering clones. Both of these potential tradeoffs would tend to equalize the lifetime seed output Of different goldenrod clones, but the extent to which this occurs can only be determined by long-term monitoring of seed set, growth and survival of individual clones. Unless we begin to understand the relationships among flowering time, seed production, and offspring establishment, it will be difficult to relate various effects of flowering phenology, such as competition for pollinators, to the abundance and distribution of plant species; that is, to community structure. Several theoretical studies have suggested that competition for pollinators can exclude a plant species from a community (e.g. Waser 1978b; Levin and Anderson 1970) and authors have suggested that successful colonization by a plant 142 species is facilitated not only by the ability to successfully establish and grow at a site, but also by having a flowering period which reduces competition for pollinators with species already present on a site (Feinsinger 1978; Frankie 1975). It does appear that competition for pollinators reduces seed set (Waser 1978a; Zimmerman 1980a; S, graminifolia in the present study) and it is likely that this could result in selection for reduced overlap in flowering time between competing species (e.g. Mosquin 1971; Waser 1978a; Pleasants 1980). However, it is not clear to what extent reductions in seed set caused by competition for pollinators prevent coexistence of plant species. The reductions in seed set caused by competition for pollinators have been reported to be approximately 222 in Polemonium (Zimmerman 1980a), 252 in IpomOpsis and 402 in Delphinium (Waser 1978a). In S, graminifolia, the percentage of filled seeds in the early-flowering clones is 542 lower than the seed set of the experimental crosses (Table 10). If competition for pollinators was responsible for approximately 702 of the reduction in seed set, then competition for pollinators caused approximately a 382 reduction in seed set in the early-flowering clones relative to the experimental crosses. Even if these reductions in seed set occurred over the entire flowering season, how*much affect would a 25-402 reduction in seed set have on the maintenance of population sizes? First off, it is clear that all plant species which co-occur are not capable of utilizing all areas of a site for germination and establishment; space which is not colonized by one plant species is not necessarily Open to colonization by others. The amount of space available for establishment in a field is partly a function of the 143 plants themselves, e.g. seed size, germination requirements, and dispersal ability (Werner 1976; Grubb 1977; Harper 1977; Gross 1980). Hence, it is likely that edaphic conditions and microenvironmental features play a larger role in maintaining diversity in plant communities than does competition for pollinators (see also Brown and Kodric-Brown 1979; Rodric-Brown and Brown 1979). Solidago graminifolia shares pollinators with a group of weedy plants (Table 2, Figure 20) that are not typically successful at invading thickly vegetated sites. Yet, S, graminifolia is a common component of prairie communities and wet areas in abandoned fields which are heavily vegetated (Werner 1976). It is unlikely that clovers (Trifolium) and sweet clovers (Melilotus) could displace S, graminifolia from a plant community even with 1002 overlap in flowering time. It is more likely that they would exert strong selection pressure for later flowering in S, graminifolia. Perhaps the greatest challenge to investigators studying competition for pollinators is to integrate reductions in seed set due to competition into the myriad of factors affecting the recruitment of individuals of different plant species in plant communities. CHAPTER 5 SUMMARY Investigation of the relationships among flowering time, insect visitors, and seed set of individual plants of four species of co- occurring goldenrods (Solidago spp.) lent insight into the processes which can select for flowering time in natural plant communities. Major results follow: 1. Within the population of each species of goldenrod, there were great differences among the flowering phenologies of clones (S, graminifolia, S, canadensis, and S, nemoralis) or ramets (S, juncea). There were also differences among the flowering phenologies of the four species of goldenrod. 2. All four species of Solidago exhibited significant differences in the percentage of filled seeds among clones which flowered at different times during the 1980 flowering season. Early-flowering clones had lower percentages of filled seeds than late-flowering clones of _S_. canadensis, _S_. graminifolia, and _S_. nemoralis. In contrast, S, juncea ramets showed a decrease in the percentage of filled seeds over the 1980 flowering season. 3. Clones of S, canadensis had a continuous increase in the percentage of filled seeds over two consecutive flowering seasons (1979 and 1980) suggesting that, at least for S, canadensis, the observed patterns in seed production per flower (percentage of filled seeds) may be general. 4. Early-flowering clones of S, canadensis, S, graminifolia, and S, nemoralis produced fewer total seeds than late-flowering clones; late-flowering ramets of S, juncea produced fewer total seeds than 144 145 early-flowering ramets. 5. There were highly significant positive correlations between the 1979 and 1980 relative phenology ranks (early to late-flowering) of S, canadensis clones and between the percentage of filled seeds of S, canadensis clones which flowered in 1979 and 1980. 6. Apis mellifera, the introduced honeybee, was the major pollinator of S, canadensis, S, ggaminifolia, and S, nemoralis. Seasonal changes in the abundance of honeybees on goldenrods were correlated with differences in seed set over the flowering season. 7. Solidago juncea was visited mainly by small, native bees and beetles; there was no evidence for a correlation between pollinator abundance and seed set in this species. 8. Overlap in the flowering periods Of goldenrods and introduced plant species appeared to be a factor influencing the abundance of honeybees on different species of Solidago. 9. Epicauta pennsylvanica (blister beetles) were flower predators which appeared to cause reductions in seed set for S, canadensis, S, graminifolia, and S, juncea. However, only in S, graminifolia did Epicauta clearly have a differential effect on the seed set of clones in different phenology groups. 10. Experimental crosses performed on S, canadensis, S, graminifolia, and S, juncea suggested that seed set was not always limited by pollinators or flower predators; physiological or genetic factors were also important determinants of seed set. 11. In S, canadensis, the percentage of filled seeds was pollinator (or pollen) limited across the entire flowering season, but the maximum potential seed set at any point in time was limited by 146 physiological or genetic factors. 12. In Solidago graminifolia the seed set of early-flowering clones was limited by pollinators or by flower predators; late- flowering clones appeared tO have reached maximum potential seed production. 13. It appeared as if seed production per'S, juncea ramet was close to the potential maximum over the entire flowering season, and it was not possible to determine which factors were most important in producing the differences in seed set for ramets which flowered at different times. 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CLONE 10 47 41 31 30 19 18 14 61 60 49 16 40 48 Solidagoggraminifolia 155 OPEN CROSSES 39.07 13.74 29.17 86.51 22.38 56.06 18.89 59.79 41.74 53.94 49.73 41.49 BAG CROSSES 12.82 0. 83.47 0. 62.50 BAG CONTROLS CLONE 10 13 16 17 18 19 23 26 q d. a) L 30 34 37 39 41 42 43 44 49 81 C .J 90 C J 97 99 107 109 120 122 129 132 154 155 156 158 174 175 176 177 156 Solidago canadensis BAG CROSSES 70.48 63.16 38.98 60.34 49.80 7.69 10.34 69.87 73.49 51.61 80.71 55.33 38.24 76.30 1.18 83033 13.12 82074 30.79 71.11 38.89 69.09 21.82 38.97 31.38 49.03 17.89 5.56 59.94 78.02 57.42 5.36 70.42 0. 0. 57094 84.64 OPEN CROSSES 32.06 18.94 29.05 33.33 25.38 77.08 20.98 61.82 56.74 38.75 17.72 68.25 46.67 47.64 63.73 64.38 15.67 38.65 65.08 78.63 48.14 36.03 37.55 23.53 88.57 31.57 65.38 60.26 0. 36.73 44.75 60.53 57.14 31.99 20.29 25.30 52.34 75.12 62.45 64.57 BAG CONTROLS 4.21 5.97 1.71 3.53 0.82 0. 0. 10.38 0.81 0. 6.11 3.56 6.77 27.40 0. 1.59 3.49 13.34 12.90 7.86 0.88 12.11 3.58 13.93 0. 9.41 4.47 0. 2.45 6.30 6.80 0. 3.49 5.38 0. 4.48 11.21 157 Solidago iuncea CLONE RAHET \IOJDJGJDJ HOFJFJP-JH 0.... “HMHP‘JH O O- m L" H 0'1 0 14.0 13.2 25.0 41.0 55.3 54.2 60.4 60.3 52. 51.2 37.0 33.4 90.2 86.4 87.2 11.0 5.0 12. 12.1 6.0 OPEN CROSSES 31.71 28.13 8.16 6.35 25.61 31.25 27.87 18.52 35.38 18.60 21.05 8.33 14.29 0. 31.11 34.78 20.69 0. 8.70 0. 13.33 1.56 19.48 21.43 16.46 6.25 0. 0. 158 APPENDIX B Data on Phenology, Seed Set, and Size of Individual Clones and Ramets of Solidago app. in 1980. For S. nemoralis and S. juncea, the value to the left of the decimal point in the CLONE RAMET -column designates the clone; the value to the right of the decimal point designates the ramet on which measurements were made. Data are reported only for clones (and ramets) with seed set measurements. PHENGROUP is the phenology group assigned. MAX MONTH AND MAX DAY designate the maximum flowering date (MFD) assigned. PCT FILLED SEEDS is the percentage of filled seeds. Volume of seeds is given in ml for individual ramets of S. juncea and S. nemoralis, and as the mean of 8 ramets for clones of S. canadensis and S. graminifolia. Ramet height is given in cm for individual ramets of S. nemoralis and as the mean of 8 ramets for clones of S, canadensis. See METHODS for further details. PHEN CLONE GROUP 2 4 7 8 10 13 15 16 17 18 19 23 ‘1 s 27 a, L 29 30 34 37 38 4o 41 42 43 44 46 4s 49 53 s: 85 9o 95 97 99 103 106 107 109 120 122 129 132 138 154 155 156 158 141 174 “(duh-HNuuuu"NNNNNNHHHNOJNNNOJHNNHNHPJNNNPJNNHNHNNNNNNNN MAX MONTH QOOO'OVOQ‘O'OQQ‘OQ'O‘O'O'OQ‘O‘O‘O‘O‘OQQ‘OQ‘OQQ‘OQ‘OQ‘O‘O‘OQQQ‘OfiQO‘O‘O‘O‘O‘O‘O 159 Solidago canadensis HAX DAY PCT FILLED SEEDS 45.00 22.66 38.73 55.48 34.56 30.76 21.34 36.15 5.61 30.43 18.81 30.76 25.20 42.02 36.61 38.58 50.43 47.37 35.55 24.82 52.74 37.60 30.72 44.30 64.45 '39.12 51.81 53.94 34.03 40.66 7.80 19.48 18.37 51.76 22.43 8.81 31.07 43.55 8.41 0.83 39.12 42.37 56.47 11.49 40.28 23.29 20.58 13.42 48.95 13.28 VOLUME 0F SEEDS 150.63 52.50 148.13 94.37 105.25 56.13 115.62 104.25 156.88 96.50 148.75 205.88 127.87 237.50 139.88 36.88 215.63 167.38 96.25 54.25 59.38 181.88 179.75 170.63 100.00 73.12 53.75 96.87 166.88 59.00 104.37 62.50 83.12 79.37 34.13 57.50 200.63 121.25 79.37 110.62 87.50 126.25 64.37 70.62 72.50 113.12 125.00 209.38 193.75 RAHET HT 90.50 82.25 96.50 122.25 127.87 76.75 111.75 104.87 97.33 109.44 117.31 113.37 133.57 101.75 135.75 121.62 127.00 112.62 115.87 113.50 109.12 148.38 100.12 115.37 121.17 112.75 111.25 93.25 110.50 120.75 124.50 98.75 RAHETS PER CLONE 67 22 47 115 68 60 54 63 29 126 23 34 20 26 32 14 10 83 25 130 45 70 93 83 97 64 29 19 70 76 57 52 36 75 27 34 69 33 44 67 75 13 89 67 127 90 38 36 4 160 Solidago canadensis PCT VOLUME PHEN MAX MAX FILLED OF CLONE GROUP MONTH DAY SEEDS SEEDS 175 3 9 23 63.15 134.38 176 3 9 18 51.90 872.50 177 3 9 23 57.33 55.63 63200 3 9 15 52.70 143.13 RAMET HT 110.50 RAMETS PER CLONE 21 6 18 213 161 Solidggggjuncea PCT’ VOLUME CLONE PNEN MAX MAX FILLED OF RAMET GROUP MONTH DAY SEEDS SEEDS 1.1 2 8 18 12.73 40 1.2 3 8 13 8.65 20 2.1 2 8 18 23.68 20 2.2 2 8 18 25.45 20 2.3 2 8 13 24.76 ' 25 2.4 2 8 18 13.46 9 3.1 3 8 9 28.85 3 3.2 1 8 9 12.93 10 3.3 2 8 9 7.41 5 3.4 2 8 18 19.44 6 5.0 2 8 13 17.54 12 6.0 1 8 4 14.02 1 7.0 1 8 4 29.41 5 8.0 1 8 4 10.91 5 10.1 1 8 13 12.26 1 10.2 1 8 9 1.98 2 10.3 1 8 9 9.43 1 10.4 3 8 18 5.93 5 10.5 3 8 18 6.78 2 11.0 1 8 9 11.32 5 12.1 1 8 4 9.80 4 12.2 1 8 4 9.80 10 12.3 2 8 18 8.57 15 12.4 3 8 22 1.82 2 13.1 2 8 4 37.27 21 13.2 2 8 4 22.33 30 13.3 3 8 22 3.51 20 13.4 2 8 13 12.96 32 13.5 3 8 22 2.88 13 14.0 1 7 29 15.69 45 15.1 3 8 18 3.77 20 15.2 3 8 27 10.28 12 15.3 3 8 27 1.96 14 15.4 3 8 27 6.67 7 15.5 3 8 27 34.95 1 16.1 2 8 9 36.79 15 17.0 2 8 9 13.16 --- 18.0 1 8 4 34.31 12 19.0 1 8 4 10.68 10 20.0 1 8 4 39.64 9 21.0 2 8 18 15.24 3 22.0 3 8 18 1.80 9 24.0 3 8 22 27.12 5 25.0 2 8 18 6.73 3 26.0 1 7 29 16.04 3 27.0 2 8 13 44.86 20 28.1 1 8 4 39.60 5 28.3 - 2 8 22 11.32 9 29.1 2 8 9 35.85 11 29.2 2 8 9 42.02 8 162 Solidago juncea PCT voLunE 010»: PHEN HAX MAX FILLED or RAHET 88009 near» 041 SEEDS 58:05 30.1 1 7 29 31.73 1 30.2 1 7 29 30.63 10 30.3 1 7 29 39.05 6 30.4 1 7 29 44.86 15 30.5 1 8 4 25.74 10 30.6 1 8 4 12.04 5 30.7 2 8 4 14.71 5 32.1 1 8 4 24.04 1 32.2 1 7 29 12.62 2 32.3 1 7 29 10.68 3 32.4 1 8 4 36.54 15 32.5 1 7 29 14.56 6 33.1 1 7 29 33.33 17 33.3 1 8 9- 8.57 7 33.4 2 8 13 0. 1 33.5 2- 8 9 1.85 10 34.0 2 8 18 28.18 3 35.0 2 8 13 13.21 5 36.0 2 8 9 2.91 10 37.0 1 8 4 12.75 10 38.0 2 8 18 19.63 15 39.0 1 8 4 3.92 1 40.0 1 8 4 34.95 10 41.0 2 8 9 51.82 1 42.0 1 8 4 52.88 15 43.0. 1 8 4 38.24 10 44.0 2 8 13 20.37 13 45.0 1 8 4 38.61 20 46.0 1 8 4 15.45 12 47.1 1 8 4 18.52 10 47.2 1 8 4 26.09 3 47.3 1 8 4 34.26 15 48.0 2 8 18 41.12 5 49.0 2 8 13 33.93 3 50.0 1 8 4 1.98 3 51.1 2 8 13 18.80 10 51.2 1 8 4 26.13 5 52.0 2 8 9 11.21 3 54.1 3 8 18 3.81 16 54.2 3 8 22 13.64 2 55.1 3 8 22 14.85 15 55.2 3 8 22 38.61 1 55.3 3 8 22 21.78 4 55.4 3 8 27 21.10 1 55.5 3 8 27 8.77 5 56.0 3 8 18 16.83 3 57.2 1 8 4 6.93 5 58.0 1 7 29 2.83 10 59.1 1 8 4 46.15 2 60.1 2 8 18 16.51 5 163 Solidago uncea PCT VOLUME CLONE PHEN MAX HAX FILLED OF RAHET GROUP HONTH DAY SEEDS SEEDS 60.2 3 8 ’22 13.33 3 60.3 3 8 22 9.82 3 60.4 2 8 18 24.53 7 61.0 2 8 18 23.08 10 62.2 2 8 13 57.28 10 63.0 2 8 13 45.19 3 64.0 3 8 22 6.60 15 63.1 2 8 18 9.62 10 65.2 2 8 18 7.35 15 65.3 2 8 18 11.43 10 67.1 3 8 22 0.93 12 67.2 3 8 18 0. 55 67.3 3 8 18 0.98 11 67.4 3 8 18 0. 15 67.5 3 8 18 0. 10 68.1 2 8 18 17.31 25 68.2 3 8 27 0. 10 68.3 3 8 18 1.96 20 68.4 3 8 18 0.95 25 68.5 3 8 22 0.94 20 69.0 2 8 13 33.64 29 72.1 3 8 27 2.86 25 72.2 3 8 27 2.75 8 73.1 1 7 29 33.04 16 73.2 1 7 29 27.10 18 73.3 1 8 4 33.33 20 73.4 1 8 4 27.52 13 73.5 1 8 4 9.09 9 73.6 3 8 18 4.72 3 74.0 2 8 18 10.19 10 75.0 1 8 9 43.32 10 76.1 3 8 22 13.38 10 76.2 3 8 13 1.94 4 76.4 3 8 18 3.39 6 76.3 3 8 22 1.96 3 77.0 3 8 27 12.38 14 78.1 3 8 22 34.82 9 78.2 3 8 22 2.78 1 78.4 2 8 18 23.81 5 79.1 3 8 18 21.78 13 79.2 3 8 18 10.28 8 79.3 1 8 9 21.78 5 79.4 2 8 13 14.55 3 79.5 2 8 18 22.81 15 80.0 2 8 9 10.89 20 81.1 2 8 9 2.94 20 81.2 2 8 9 3.67 30 81.3 2 8 9 2.67 10 81.4 2 8 18 4.35 15 81.5 3 8 22 6.36 13 164 Solidago juncea PCT VOLUME CLONE PHEN MAX MAX FILLED OF RAMET GROUP MONTH DAY SEEDS SEEDS 82.1 2 8 9 11.65 10 82.2 2 8 13 15.24 5 82.3 2 8 9 2.91 3 82.4 3 8 22 0. 10 83.1 3 8 22 4.90 25 83.2 3 8 18 0. 29 83.3 3 8 27 1.79 10 83.4 3 8 18 0. 30 83.5 3 8 .2 1.98 15 84.1 2 8 18 6.93 10 84.2 2 8 18 8.65 33 85.0 2 8 9 19.05 12 86.1 1 8 4 0. 1 86.2 2 8 9 0. 25 86.3 2 8 4 0. 10 86.4 3 8 18 4.59 10 86.5 3 8 22 0.91 10 87.1 2 8 18 2.94 5 87.2 3 8 22 2.63 --* 88.0 1 8 4 1.90 10 89.0 2 8 13 2.65 28 90.1 2 8 18 0. 8 90.2 2 8 22 0. 8 90.3 2 8 22 0. 20 90.4 2 8 13 0.94 10 91.0 2 8 18 16.51 11 CLONE ‘OGDbOJP'Jt-A 12 14 16 17 18 19 r) L. 21 30 31 32 33 34 7c- 5’s. '2‘ —b 37 4O 41 43 C J 46 47 48 49 C .J 54 60 61 22 2-100 f PHFN GROUP wwHHMNHHHMo-or-Jwt-JHNHUv—uwwMUMrJr-JHHIJMHMHMUtJ 165 Solidago_graminifolia MAX MONTH QQQmQ‘OCDCOC'O‘OGJ‘OOQOOQO®CD®~O~O~OQ~O~O~OCD~O~O~O~OCD~OGD~O MAX DAY F.) P-J 0mmOO~O~CODGJHJJ0~HO~O~O~O~O~CDCDLDO~O~HCOHO~0~OO~O~O~O~UJO~€DO~ fJ FJH H 90 "J f-J H 7‘.) DJ 8‘.) f-J H f-J .“J L) PCT FILLED SEEDS 65.00 55.90 80.37 24.26 28.17 25.70 15.08 23.95 17.85 11.2 34.79 29.12 39.61 69.00 39.61 25.92 33.12 20.77 56.94 42.03 59.85 25.79 29.38 38.52 54.92 45.49 18.20 27.77 14.06 21.75 34.94 41.30 39.75 8.23 15.90 51.57 40.18 VOLUME OF SEEDS 77.14 111.87 48.13 72.14 18.33 73.75 31.87 60.00 23.33 68.12 71.87 54.38 51.88 120.00 57.86 203.75 64.17 105.00 94.37 41.25 47.50 31.87 RAMETS PER CLONE 8 41 75 87 80 181 122 64 138 100 97 92 14 56 26 53 92 33 14 79 r, & 28 88 18 34 q l- 47 75 67 27 53 41 12 58 _* CLONE RAMET o O o OONOOOOOOOO O O O #NHOQOO-G&N O ”pg-a... PNEN OROUP F‘HNuNNNuuuuu-ou”HnfluuuuuuwnuuuuwunNo-oHuuHHNNNNNNuHit-NH 166 Solidago nemoralis MAX MONTH Q‘O‘O’O'O‘O‘O’O'O‘O‘OQ‘Q‘OQ‘OQQQQ‘OQQ’OQ’O‘OQ‘QO‘QQQ‘OQQQQQQO‘OO'0‘0‘090 MAX DAY 3 11 11 11 18 11 11 -11 11 18 18 11 11 18 11 11 3 11 11 18 11 18 18 18 3 11 11 18 18 18 18 18 18 11 11 11 11 3 3 18 18 18 18 18 11 18 18 11 3 11 PCT FILLED SEEDS 23.24 23.48 1.98 37.86 34.53 40.37 80.77 61.74 23.68 65.71 51.49 37.14 62.86 3.77 12.50 32.38 20.39 26.47 18.81 54.63 62.62 19.80 23.08 29.81 26.13 27.18 26.61 39.81 50.96 54.29 34.63 39.29 34.65 59.22 38.36 33.98 72.75 22.64 48.48 57.01 73.27 36.73 33.21 54.13 47.17 35.40 40.18 76.92 25.47 32.11 TOT SEED VOLUME 20 20 13 10 20 13 25 30 25 15 20 15 20 15 20 10 5 20 13 10 20 10 10 40 7 35 20 20 13 13 40 23 45 25 20 20 5 3 20 15 10 10 60 10 50 15 25 50 30 20 RAMET MT 59 61 45 45 50 47 52 38 44 33 57 45 52 40 52 58 43 42 48 33 50 49 52 62 54 61 51 65 45 44 31 41 26 46 59 47 33 59 53 54 CLONE RAMET 64.3 65.0 66.0 67.0 69.0 71.0 73.0 74.0 77.0 78.0 79.1 79.2 80.1 81.0 83.0 84.1 83.0 87.0 88.1 89.0 90.0 93.0 94.0 101.0 102.0 103.2 104.0 105.0 108.1 108.2 108.3 109.2 110.0 111.0 112.0 116.0 117.0 118.0 119.0 120.0 121.0 122.0 125.0 126.0 127.0 128.0 130.0 131.0 132.1 133.0 PHEN GROUP NNNN‘NNF‘FNM"N"M“NNUA“Nuuflnfi‘fouufluNt‘NNNMNHflNNMNUNNU-‘NNH Solidago nanoralis MAX MONTH 0005007050Q‘O'O'OQ'O'OQ'O‘OQQQ‘O‘O‘O’O'OQ'OVOOVO’OQ‘OO'OQ'O00007000000000 167 MAX DAY 11 18 11 11 11 18 18 11 11 11 11 11 18 11 11 11 11 11 18 18 18 11 11 11 18 18 11 11 11 11 11 11 18 18 11 11 18 11 11 18 11 PCT FILLED SEEDS 24.77 46.79 71.29 49.04 36.27 59.80 31.07 62.75 37.74 54.21 29.09 23.00 5.94 28.70 12.84 54.21 47.06 55.24 3.92 27.78 57.52 9.90 9.91 43.81 3.96 43.54 36.27 31.13 40.33 34.31 22.12 18.27 1.82 ‘ 0.94 51.43 8.82 11.76 37.62 31.23 40.47 38.10 31.82 6.80 33.01 1.98 22.32 26.85 37.61 24.27 23.36 TOT SEED VOLUME 45 80 25 15 5 3 12 20 10 20 20 10 105 13 35 40 15 15 35 25 2 10 20 10 15 35 5 100 45 35 5 10 10 20 3 23 15 30 20 35 10 20 15 10 30 10 15 40 13 RAMET HT 55 62 65 51 63 56 49 52 54 29 39 49 50 45 56 48 45 72 45 44 53 31 63 80 74 30 50 47 41 57 25 51 63 70 36 58 45 52 53 55 57 36 65 29 CLONE RAMET 134.0 136.0 137.0 138.0 139.0 141.0 142.0 143.0 145.0 146.0 147.0 148.0 149.0 150.0 151.0 152.1 152.2 153.0 154.0 155.0 156.1 157.0 158.1 158.2 158.3 159.0 FHEN GROUP NuuuuuuuwuwpuroMqu-Hmumwwu—u 168 Solidago nemoralis MAX MONTH ~O‘O‘O‘O‘O‘O‘O‘O‘OO‘O‘O‘OO‘OOQ‘O‘O‘O‘OQflO‘OO MAX DAY 11 11 11 11 11 11 11 11 18 11 11 18 11 11 18 18 18 18 18 18 11 PCT FILLED SEEDS 20.59 3.77 50.00 39.42 29.91 28.85 32.52 28.71 24.78 25.00 24.04 14.02 9.80 43.40 9.52 18.27 11.54 38.46 2.94 25.74 66.96 51.75 31.07 37.50 38.18 33.33 TOT SEED VOLUME 20 10 25 15 25 10 15 10 25 25 30 5 25 20 10 20 5 10 30 15 55 15 10 5 10 10 RAMET HT 53 47 36 47 76 46 47 36 46 45 43 37 48 51 45 59 52 20 62 66 56 57 43 45 59 169 APPENDIX C Data on Flowering Phenology and Insect Visitors for Individual Clones and Ramets of Solidago app. on Several Census Dates in 1980. Data are presented from census dates which span the bulk of the flowering season for each species; census dates from very early and very late in the flowering season are not presented. For'S, nemoralis and S. juncea, the value to the left of the decimal point in tfie CLONE cqumn designates the clone; the value to the right of the decimal point designates the ramet on which measurements were made. Data are reported only for clones (and ramets) with seed set measurements. FF, F, and BUD are the percentage of heads (capitula) in the past flowering, flowering, and bud stages, respectively. APM is the number of Apia counted during visual counts on each census date. BOMB is the number of Bombus spp. counted. BP PE is the number of Epicauta ennsylvanica (Blister Beetle) counted. CH PE is the number of uliognathus pennsylvanicus (Soldier Beetle) counted. DAY and MONTH designate the census date. PCT FILL is the percentage of filled seeds. Data are provided for both Solidago canadensis var. scabra and S. canadensis var. canadensis; in the text, S, canadensis var. scabra is referred to as S. canadensis. See METHODS and STUDY SYSTEM for further details. 17C) Solidago nemoralis CLONE FF F BUD DAY NONIH CLONE FF r sun any "out" 2.0 55 45 0 11 9 20.2 100 o o 26 . 9 2.0 90 10 0 18 9 20.2 o 40 5o 3 9 2.0 100 0 0 26 9 24.1 0 60 40 11 9 2.0 5 9S 0 3 9 24.1 0 100 0 18 9 4.0 0 100 0 11 9 24.1 60 40 0 26 9 4.0 5 95 O 19 9 24.1 0 0 100 3 9 4.0 95 5 0 26 9 24.2 0 90 10 11 9 4.0 ’ 0 0 100 3 9 24.2 10 90 0 18 9 5.0 10 90 0 11 9 24.2 85 15 0 26 9 5.0 15 85 0 18 9 24.2 0 0 100 3 9 5.0 70 30 0 26 9 26.0 15 85 0 11 9 5.0 0 20 80 3 9 26.0 55 45 0 18 9 6.0 20 80 0 11 9 26.0 95 5 0 26 9 6.0 85 15 0 18 9 26.0 0 25 75 3 9 6.0 100 0 0 26 9 27.0 85 15 0 11 9 6.0 0 40 60 3 9 27.0 100 0 0 18 9 8.0 0 50 50 11 9 27.0 100 0 0 26 9 8.0 10 90 0 18 9 27.0 70 30 0 3 9 8.0 95 5 0 26 9 29.0 0 100 0 11 9 8.0 0 0 100 3 9 29.0 15 85 0 18 9 9.0 0 100 0 11 9 29.0 98 2 0 26 9 9.0 40 60 0 18 9 29.0 0 0 100 3 9 9.0 100 0 0 26 9 30.1 0 95 5 11 9 9.0 0 0 100 3 9 30.1 10 90 0 18 9 10.0 0 100 0 11 9 30.1 100 0 0 26 9 10.0 70 30 0 18 9 30.1 0 0 100 3 9 10.0 100 0 0 26 9 30.3 0 70 30 11 9 10.0 0 5 95 3 9 30.3 15 85 0 18 9 11.0 0 100 0 11 9 30.3 100 0 0 26 9 11.0 5 95 0 18 9 30.3 0 0 100 3 9 11.0 100 0 0 26 9 31.0 10 90 0 11 9 11.0 0 0 100 3 9 31.0 70 30 0 18 9 12.2 0 100 0 11 9 31.0 100 0 0 26 9 12.2 5 95 0 18 9 31.0 0 15 85 3 9 12.2 95 5 0 26 9 32.0 0 20 80 11 9 12.2 0 0 100 3 9 32.0 0 100 0 18 9 14.0 0 70 30 11 9 32.0 25 75 0 26 9 14.0 15 85 0 18 9 32.0 0 0 100 3 9 14.0 98 2 0 26 9 33.0 0 90 10 11 9 14.0 0 0 100 3 9 33.0 0 100 0 18 9 19.0 0 50 50 11 9 33.0 95 5 0 26 9 19.0 0 100 0 18 9 33.0 o o 100 3 9 19.0 100 0 0 26 9 34.0 0 20 80 11 9 19.0 0 0 100 3 9 34.0 0 100 0 18 9 20.1 20 80 0 11 9 34.0 98 2 0 26 9 20.1 85 15 0 18 9 34.0 0 0 100 3 9 20.1 100 0 0 26 9 35.0 95 5 0 11 9 20.1 0 40 60 3 9 35.0 100 0 0 18 9 20.2 30 70 0 11 9 35.0 100 0 0 26 9 20.2 80 20 0 18 9 35.0 30 70 0 3 9 CLONE 36.1 36.1 36.1 36.1 36.2 36.2 36.2 36.2 38.1 38.1 38.1 38.1 38.2 38.2 38.2 38.2 38.3 38.3 38.3 38.3 39.1 39.1 390‘ 39.1 39.2 39.2 39.2 39.2 41.0 41.0 41.0 41.0 43.0 43.0 43.0 43.0 44.0 44.0 44.0 44.0 47.0 47.0 47.0 47.0 ‘900 49.0 49.0 49.0 56.1 56.1 FF 35 100 50 90 n O Q 0 b O O 00°OOOUOOMOOOOUOOOMOOMOOO O DUD 0 9 00000000 100 p O O OOUOOOOOOOOOOOOOOO 171 Solidago nemoralis DAY MONTH 11 18 26 3 11 18 26 3 18 26 3 11 18 26 3 11 18 26 3 11 18 26 QQOO'O'OQQ'O'OQ'OQQQCO‘O‘QQOOQOQ’OO"0000‘0‘0000‘0000'O‘O'OQ'O CLONE 36.1 56.1 56.2 56.2 56.2 36.2 57.2 57.2 57.2 57.2 37.3 57.3 57.3 57.3 58.1 58.1 58.1 58.1 58.2 58.2 38.2 58.2 58.3 58.3 58.3 58.3 61.2 61.2 61.2 61.2 62.1 62.1 62.1 62.1 62.2 62.2 62.2 62.2 63.0 63.0 63.0 63.0 64.1 64.1 64.1 64.1 64.2 64.2 64.2 64.2 0!" \J OOOOOOOMOOOOOO QM 00 100 50 65 100 40 100 IUD 5 000000000 8-0 O O N 000 100 40 100 DAY MONTH 26 3 11 18 26 3 11 18 OOOQ'O'OQ'OQ‘OOVO'O'OQ‘OO'O'O'OVO‘O'O'OQ‘OO'O'O'OOVOQQQ‘O00000000000000 CLONE 64.3 64.3 64.3 64.3 65.0 65.0 65.0 65.0 66.0 66.0 66.0 66.0 67.0 67.0 67.0 69.0 74.0 77.0 78.0 78.0 78.0 78.0 79.1 79.1 79.1 79.1 79.2 79.2 79.2 79.2 80.1 80.1 .b on. O“ DUD fl '0 O '0 0 GM 000000000000000004500000 “ 00 OMMO 6.. O 0 oouooouooooooouooo '0 172 Solidago nemoralis DAY MONTH 11 18 26 3 11 18 26 0050000000000Q‘O'OQ'OQ‘OQQQ'O'O'OQQQ‘QQQQOQOQO‘O‘OQQQ‘OQQ‘OO CLONE 80.1 80.1 81.0 81.0 81.0 81.0 83.0 83.0 83.0 83.0 84.1 85.0 83.0 85.0 85.0 87.0 87.0 87.0 87.0 88.1 88.1 88.1 88.1 89.0 89.0 89.0 89.0 90.0 90.0 90.0 90.0 93.0 93.0 93.0 93.0 94.0 94.0 94.0 94.0 101.0 101.0 101.0 101.0 102.0 102.0 102.0 102.0 103.2 103.2 103.2 FF 100 \J 0410000004.!00 40 100 23 85 100 DUD an n 0 0000000000 p 0 u N 0 00‘80000000000000 hot- 00 0° '0 0000000 DAY MONTH 26 3 11 18 26 3 11 18 26 ”0'000000900000000000'0000507000000000'00‘00‘00000'000'000’0'. CLONE 103.2 104.0 104.0 104.0 104.0 105.0 103.0 105.0 105.0 108.1 108.1 108.1 108.1 108.2 108.2 108.2 108.2 108.3 108.3 108.3 108.3 109.2 109.2 109.2 109.2 110.0 110.0 110.0 110.0 111.0 111.0 111.0 111.0 112.0 112.0 112.0 112.0 116.0 116.0 116.0 116.0 117.0 117.0 117.0 117.0 118.0 118.0 118.0 118.0 119.0 O~ OOOOLMOO 40 100 DUO 04 '0 00005.00000 0"0 00M ~ “0 0000 100 an. 0 O 00450 (ad 0— on 9 O 0 MOOOOUOOOOOOOOOOOOOOUOOO00000 Q Q 173 Solidaggrnemoralis DAY MONTH 3 11 18 26 3 11 18 26 3 11 18 26 3 11 18 26 3 11 18 26 3 11 18 26 3 11 18 26 OOQOO‘QOQOQOQQQQ‘OQQOQOQQ'OO’O000050000000050000700700000 CLONE 119.0 119.0 119.0 120.0 120.0 120.0 120.0 121.0 121.0 121.0 121.0 122.0 122.0 122.0 122.0 125.0 125.0 125.0 125.0 126.0 126.0 126.0 126.0 127.0 127.0 127.0 127.0 128.0 128.0 128.0 128.0 130.0 130.0 130.0 130.0 131.0 131.0 131.0 131.0 132.1 132.1 132.1 132.1 133.0 133.0 133.0 133.0 134.0 134.0 134.0 100 100 F DUO 70 0 2 0 5 95 40 0 5 0 0 0 80 20 10 90 100 0 10 0 0 100 15 85 100 0 0 0 0 100 30 0 0 0 0 0 75 25 80 0 0 0 0 0 70 30 100 0 90 0 0 0 0 100 80 20 85 0 10 0 3 95 100 0 90 0 2 0 0 100 90 10 40 0 2 0 30 70 85 13 90 0 2 0 0 100 95 0 35 . 0 0 0 13 83 90 0 50 0 0 DAY MONTH 18 26 3 11 18 26 3 1.1 18 26 3 11 18 26 3 11 18 26 3 11 18 26 3 11 18 26 3 11 18 26 O'OQO'O'OQ‘OO'OQ'O'OO'O‘OVOOQQ'O'O'OOQQQQ'O‘OQ‘O'O‘O'O‘OQ‘OQ'OQQQ'OQQO'O'O'O CLONE 134.0 136.0 136.0 136.0 136.0 137.0 137.0 137.0 137.0 138.0 138.0 138.0 138.0 139.0 139.0 139.0 139.0 141.0 141.0 141.0 141.0 142.0 142.0 142.0 142.0 143.0 143.0 143.0 143.0 145.0 145.0 145.0 145.0 146.0 146.0 146.0 146.0 147.0 147.0 147.0 147.0 148.0 148.0 148.0 148.0 149.0 149.0 149.0 149.0 150.0 70 15 BUD .- u- 8— v- Q 0 ND \l N O N O 0 ”O 0 U “"000“0000000150000000M00000°uu0°0°000M000000000000 00 174 Solidago nemoralis DAY MONTH fl “ 000700000000000000000‘OCQ‘OQQQ‘OOQOQ‘OQOQOO00000000000 CLONE 150.0 150.0 150.0 151.0 151.0 131.0 151.0 152.1 152.1 152.1 152.1 152.2 152.2 152.2 152.2 153.0 153.0 133.0 153.0 154.0 154.0 154.0 154.0 155.0 155.0 155.0 155.0 156.1 156.1 156.1 156.1 137.0 137.0 157.0 157.0 158.1 158.1 138.1 158.1 158.2 138.2 158.2 158.2 158.3 158.3 158.3 158.3 159.0 139.0 159.0 FF 0 60 100 O u \l 0000000000000000000000 p b O 0 100 100 40 on 0 n 0 «on N § 000000000000000000000000000000 '0 on. 0 0 93 005000000000700'0007000009000000Q‘O’OQQOOOQOQQQOQO‘OOQQQQ‘O CLONE 159.0 FF 0 F 10 DUO 90 175 Solidago nqnoralis DAY MONTH 3 9 CLONE oooooowunuuu 176 Solidago canadensis var. canadensis :9 cu . r nun APM noun 9: 98 any 95 5 4 0 0 25 30 80 0 6 0 0 1 5 30 0 0 o o o 10 0 0 o 0 0 o 15 0 0 0 0 0 0 18 o 0 0 0 0 o 23 25 75 3 0 0 7 30 100 0 8 1 0 9 5 50 o o 0 0 0 10 2 0 0 0 0 0 15 2 0 0 0 0 0 18 0 0 0 0 0 0 23 10 90 2 o 0 6 30 85 o 12 0 0 4 5 4o 0 o o 0 0 10 10 0 0 o 0 o 15 2 0 1 0 0 0 18 0 0 0 0 0 0 23 85 15 0 0 12 3 30 60 0 4 0 7 1 5 25 0 0 0 0 0 10 0 o 0 0 0 0 15 0 0 0 0 o 0 18 o 0 0 o 0 0 23 80 20 4 0 0 5 30 95 0 8 0 0 3 5 50 0 0 0 0 0 10 0 0 0 0 0 0 15 0 0 0 0 0 0 18 0 ° 0 0 0 0 0 23 5 95 1 0 0 6 30 100 0 11 o 0 1 5 85 0 0 0 0 0 10 35 0 0 0 0 0 15 20 0 0 0 0 0 18 0 0 0 0 0 0 23 40 0 3 0 0 4 3o 10 0 0 0 0 0 5 0 0 0 0 0 0 10 0 0 0 0 0 0 15 0 0 0 0 0 0 18 o 0 0 0 0 0 23 35 65 1 0 o 1 30 95 o 3 0 0 3 5 80 0 0 0 0 0 10 50 o o 0 0 0 15 40 0 o 0 o 0 18 15 0 0 0 0 0 23 9o 10 3 0 0 3 30 85 0 4 0 0 0 5 MONTH 0.00000.00000'00000000000000300000709000°Q0QQQOQ‘OQQQO CLONE 87 87 87 87 101 101 101 101 101 101 126 126 126 126 126 167 167 N 100 85 SUD .1. HO 0000000000000000 u 000M0000°0°0°0°0°0°000 APM DOMB‘ p 177 S. canadensis var. 00000000000000000000000000000000000000000000000000 000000000000000000000000000000000009‘900000000000000 canadensis EP CH PE PE 00MU00000N000009000000.00000000000000000‘00000000000 DAY MONTH 10 15 18 23 3O 5 10 13 18 23 070090900900”Q‘QQOQ‘O‘Q'O‘OOO‘O'OQ'ODQQQ'OVOO‘O‘O'OQ‘OQ70050500007007. 178 ‘S. canadensis var. canadensis EP CH PCT CLONE FF F 800 APM DOMD PE PE DAY MONTH FILL 167 93 3 0 0 0 0 0 18 9 1.47 167 100 0 0 0 0 0 0 23 9 1.47 168 0 95 3 3 0 2 4 30 8 14.58 168 25 75 0 1 0 0 0 5 9 14.58 168 75 25 0 0 0 0 0 10 9 14.58 168 90 10 0 0 0 0 0 15 9 14.58 168 98 2 0 0 0 0 0 18 9 14.58 168 100 0 0 0 0 0 0 23 9 14.58 169 0 20 80 0 0 1 0 30 8 10.59 169 15 85 0 2 0 0 0 5 9 10.39 169 65 35 0 0 0 0 0 10 9 10.59 169 85 15 0 0 0 0 0 13 9 10.59 169 100 0 0 0 0 0 0 18 9 10.59 169 100 O 0 0 0 0 0 23 9 10.59 170 0 50 50 0 0 3 1 - 30 8 5.58 170 3 95 0 0 0 0 0 5 9 5.58 170 90 10 0 0 0 0 0 10 9 5.58 170 93 5 0 0 0 0 0 15 9 5.58 170 100 0 0 0 0 0 0 18 9 5.58 170 100 0 0 0 0 0 0 23 9 5.58 173 0 0 100 0 0 0 0 30 8 7.04 173 0 73 23 4 0 9 1 5 9 7.04 173 0 100 0 0 0 0 0 10 9 7.04 173 70 30 0 1 0 0 0 15 9 7.04 173 85 15 0 0 0 0 0 18 9 7.04 173 100 0 0 0 0 0 0 23 9 7.04 CLONE OQOOOOVVVVVVOOO‘DDNMNNMN 179 Solidago canadensis var. scabra BUD 100 APM DOMD NH 00MVO0000'0“0000.30.008800’OOOD‘ONOOO‘OOMOO‘.‘OOOOHHNOMO 00°0M000000000000000000000000000000000000000000000 EP '9 M 1.8.000000094600.0000000000000000000000001100000000000900 p CH PE an. 0.0 005-0000000998”0000000000000“0°0U0u000°°~0°000fl0°flu DAY MONTH 30 5 10 15 18 23 30 5 10 13 18 23 30 3 10 15 18 23 30 0090,0000".000000000000000000000000000000000.00000. PCT FILL 45.00 45.00 45.00 43.00 45.00 45.00 22.66 22.66 22.66 22.66 22.66 22.66 38.73 38.73 38.73 38.73 38.73 38.73 55.48 55.48 55.48 55.48 55.48 55.48 34.36 34.56 34.36 34.56 34.36 34.56 30.76 30.76 30.76 30.76 30.76 30.76 21.34 21.34 21.34 21.34 21.34 21.34 36.15 36.15 36.15 36.15 36.15 36.15 5.61 5.61 g. 100 ”.0” fl .0000 “0 '0 to oooooooooooooouuooooo on “0 0000 180 canadensis var. APM 80MB 000000000-006-006400000M0N00000V0000OO‘OOUOOOOOOMOO-O0000 000°00000000000000000-000000000000000000000000000000 scabra EP CH PE PE 00000000000000000000000000000HHOO00°~N00009-800000000 00N000°06‘0HVO‘00000"‘05‘00000809‘00000000N0000000000000 DAY MONTH 10 15 18 23 30 5 10 15 18 23 30 3 10 13 ' 18 23 30 5 10 15 18 23 30‘ 5 10 13 18 23 30 5 10 15 18 23 30 5 10 13 18 23 30 5 10 15 18 23 30 5 10 15 QOQOOQQQCOO‘QQ0.000000009000000QQOOOQQQOQQQQOO'O‘Qfi'O PCT FILL 5.61 5.61 5.61 5.61 30.43 30.43 30.43 30.43 30.43 30.43 18.81 18.81 18.81 18.81 18.81 18.81 30.76 30.76 30.76 30.76 30.76 30.76 25.20 25.20 25.20 25.20 25.20 25.20 42.02 42.02 42.02 42.02 42.02 42.02 36.61 36.61 36.61 36.61 36.61 36.61 38.58 38.58 38.58 38.58 38.38 38.58 50.43 50.43 50.43 50.43 FF 95 100 60 83 100 g. DUD 0 on NO '0 00000000000000000000 181 canadensis var. APM 80MB (.4 .- Nu-o o-o to“ Ho- 09001000.-anoooouvoOuOuuoooo~uuoooou~ooooHooooonoounoo 00000000000000000000000000000000000-000000000000000 scabra EP CH PE PE 000000000000000004000000000000000000000000000000000 ”fl 000000008-.0000”“0‘0040400OOOO‘OOOOOOOOOQOO00050000006‘00 DAY MONTH 18 23 30 5 10 15 18 ‘000000000‘0000000000’000QCQ‘Q‘QOOQQQOOQQQ'O'OO009000000 PCT FILL 30.43 50.43 47.37 47.37 47.37 47.37 47.37 47.37 35.55 35.55 35.53 35.55 33.55 35.55 24.82 24.82 24.82 24.82 24.82 24.82 52.74 52.74 32.74 52.74 52.74 52.74 37.60 37.60 37.60 37.60 37.60 37.60 30.72 30.72 30.72 30.72 30.72 30.72 44.30 44.30 44.30 44.30 44.30 44.30 64.45 64.45 64.45 64.45 64.45 64.45 19 w 004 “000011000 Cu 0001 “018001-8430 100 g. DUD 100 00000000000M°0000000 9.. 00 5‘0 canadensis var. APM DOMD us Noooooa—oooouoou.omoouuooo-—uuonoounooo—HoooOur-no 0°00000000°00000000000000000000‘0000000000000000000 2922 “UNI "IV CH PE 0-0°000H"°000000000h”0°°0u06‘b.0N00000N0000000‘000000 DAY MONTH 000000000090000000000000000000000000500005000090.0000 PCT FILL 39.12 39.12 39.12 39.12 39.12 39.12 31.81 51.81 51.81 51.81 51.81 51.81 53.94 53.94 33.94 53.94 53.94 53.94 34.03 34.03 34.03 34.03 34.03 34.03 40.66 40.66 40.66 40.66 40.66 40.66 7.80 7.80 7.80 7.80 7.80 7.80 19.48 19.48 19.48 19.48 19.48 19.48 18.37 18.37 18.37 18.37 18.37 18.37 51.76 51.76 106 107 107 107 107 107 107 109 109 109 109 109 120 120 120 120 120 122 122 122 122 122 122 129 129 129 129 g. DUD \l “ u 00 0 00000000000000000U0000 on... 00 00 95 APM u cocoa—Onooooocuooooouuuouo onus-0 on.“ 0 ans-n .0003U00000000uu000‘00 183 canadensis 80MB 00000000000000000000000000000000000000000000000“N0 var. scabra EP PE pa 0000000000000005000000'OF‘00000000000000000000000000 CH PE 00000040000000000000000908-.»0000000fi00000N000000U000 DAY MONTH 10 15 18 23 30 0'00.500000.000000000000000000000000Q‘Q‘OQO'OQQ'O'OO'O'O'O'O PCT FILL 51.76 51.76 51.76 51.76 22.43 22.43 22.43 22.43 22.43 22.43 8.81 8.81 8.81 8.81 8.81 8.81 31.07 31.07 31.07 31.07 31.07 31.07 43.55 43.55 43.55 43.55 43.33 43.55 8.41 8.41 8.41 8.41 8.41 8.41 0.83 0.83 0.83 0.83 0.83 0.83 39.12 39.12 39.12 39.12 39.12 39.12 42.37 42.37 42.37 42.37 161 161 161 161 161 174 174 174 174 174 175 175 175 FF or: 00000000000000 00000000 100 100 73 g. DUO 10 100 100 30 100 100 Q 5‘ 000 O 0- 0 H 00 ooouuoooooauooooouooooouoooou 184 2222922212 var- 494 ION! 15 1 p on N “000““00083.0u008‘w00u00009“0000u00000N0u0000VH000 00000000000000000000000000000000000000000000000000 222252 8? ca 92 9: 2 0008‘000000000000000000000000000000000004000000000. u. ”N 000000000000H00000000000M"0000000000u00000009-800000 04v MONTH 18 23 30 3 10 15 18 23 30 3 10 15 30 3 10 13 18 23 30 5 10 15 18 000007000000000000000000000.00000000005000000905005000500 PCT FILL 42.37 42.37 56.47 56.47 56.47 56.47 56.47 56.47 11.49 11.49 11.49 11.49 40.28 40.28 40.28 40.28 40.28 40.28 23.29 23.29 23.29 23.29 23.29 23.29 20.58 20.58 20.58 20.38 20.58 20.58 13.42 13.42 13.42 13.42 13.42 13.42 48.95 48.95 48.95 48.93 48.95 48.93 13.28 13.28 13.28 13.28 13.28 63.15 63.15 63.15 185 _S_. canadensis var. scabra :9 cu PCT CLONE rr 9 BUD APM BOND PE PE 041 80818 FILL 175 0 90 10 9 0 0 0 18 9 63.15 175 0 100 0 3 0 0 0 23 9 63.15 176 0 0 100 0 o o 0 5 9 51.90 176 0 5 95 0 0 0 0 10 9 51.90 176 0 85 15 4 0 o 1 15 9 51.90 176 0 100 0 29 1 0 2 18 9 51.90 176 15 85 0 2 o 0 3 23 9 51.90 177 o 0 100 0 0 0 0 5 9 57.33 177 0 0 100 0 0 0 0 10 9 57.33 177 0 0 100 o 0 0 0 15 9 57.33 177 o 15 85 1 0 0 0 18 9 57.33 177 o 100 0 4 0 0 0 23 9 57.33 63200 0 0 100 0 0 0 0 30 8 52.70 63200 0 0 100 0 o 0 1 5 9 52.70 63200 0 50 50 0 0 0 0 10 9 52.70 63200 5 95 o 29 0 2 12 15 9 52.70 63200 30 7o 0 68 1 2 11 18 9 52.70 63200 60 4o 0 9 0 0 3 23 9 52.70 CLONE 000000000000000000NHNHHNNMNNNNMHM>AHo- 63 BUD 100 100 75 100 186 Solidago graminifolia APM DONG p O9 00000000000‘900004004000OONOOOOOUNOOOOMHOOOOO¢0000.”00 p. 0000000000000000000000000000000‘000000‘0000000000000 EP H0000000000‘1‘0-‘0000004N000000000MN00000-000000"H0000000 CH PE 04 N . (alt-o QNOO00000000—000000000NOONNOOOONUOHOO”QbOOOOONOOOOuO0 ” u DAY MONTH 20 24 28 0°0000000000000000000000000000000”QQOOQQQOOOQQQOOO PCT FILL 65.00 63.00 65.00 65.00 65.00 65.00 55.90 55.90 55.90 55.90 55.90 55.90 80.37 80.37 80.37 80.37 80.37 80.37 24.26 24.26 24.26 24.26 24.26 24.26 28.17 28.17 28.17 28.17 28.17 28.17 25.70 25.70 25.70 25.70 25.70 25.70 15.08 15.08 15.08 15.08 15.08 15.08 23.95 23.95 23.95 23.95 23.95 23.95 ' 17.85 17.85 ‘3 FF 65 100 100 187 Solidago graminifolia APM DOMD p. pl. nooouo.Moonooaooonooooonoo.wo°uou°o°u°uboouoovooooou 00000000000‘000000000000000000000000000000000000000 EP PE “ O 00'4”“00000000”000000000000“NN00000000M9‘00000000000“ CH PE <><3<><><><>c>c8n804636043¢:~o-u.u1910151319 up“ 09000-90 hay-6H OQNO0MN0000uu000000000 0 DAY MONTH 28 6 11 17 20 24 28 6 11 17 20 24 28 6 11 17 20 '000050909000.00'.00.00000000000000000000000.00000000900 PCT FILL 17.85 17.85 17.85 17.85 11.27 11.27 11.27 11.27 11.27 11.27 34.79 34.79 34.79 34.79 34.79 34.79 29.12 29.12 29.12 29.12 29.12 29.12 39.61 39.61 39.61 39.61 39.61 39.61 69.00 69.00 69.00 69.00 69.00 69.00 39.61 39.61 39.61 39.61 39.61 39.61 25.92 25.92 25.92 25.92 25.92 25.92 33.12 33.12 33.12 33.12 “ NM ONNUOOMON 15 80 80 10 DUD 100 188 Solidago graminifolia APM DOMD N N H 9‘ M NONNOOMOMNOOMOON0°0°N00000¢J0000009‘00N0uut‘0n0N00000 N 00000000000000000000000000000000000000000000000000 EP PE 00000000008‘0000“"000000*.000'0000001.0000000‘00000“NoO CH PE 00 8‘... 000-.0OOOOODOD‘OOOOUO‘OOOOI‘MHOOM.V0OOONO‘OOOOOOOOOOQMN DAY MONTH 11 17 20 24 '00000000000000000000000000000.0000000000000500.0090‘. PCT FILL 33.12 33.12 20.77 20.77 20.77 20.77 20.77 20.77 56.94 56.94 56.94 56.94 56.94 56.94 42.03 42.03 42.03 42.03 42.03 42.03 59.85 59.83 39.85 59.85 59.85 39.85 23.79 25.79 25.79 25.79 25.79 25.79 29.38 29.38 29.38 29.38 29.38 29.38 38.52 38.52 38.52 38.52 38.52 38.52 54.92 34.92 54.92 54.92 54.92 54.92 30 50 15 65 50 BUD 100 189 Solidago graminifolia APM BOMB ” th’oac’o--c>¢>c,<>cnuac>cpcpc>o.o-o101cuo»-u4c><>c>c><>~9c>c>u-<>~o<>c>¢>c>c>c>sac><>-<>~494¢,c5 00000000000000000000000000000000000000000000000000 EP PE 0 H “000008.000000000000040000.“0000809-‘000000000090000000‘ CH PE “ N ”0008-9180:-00000040000940.000°V“0000\J“00M0000080004000008‘0 p. p b 5.. DAY MONTH 20 24 28 6 11 17 20 24 28 6 11 17 20 24 28 6 11 17 20 24 28 0.000000000000000000000000000000000000000000009000. PCT FILL 45.49 45.49 45.49 45.49 45.49 45.49 18.20 18.20 18.20 18.20 18.20 18.20 27.77 27.77 27.77 27.77 27.77 27.77 14.06 14.06 14.06 14.06 14.06 14.06 21.75 21.75 21.75 21.75 21.75 21.75 34.94 34.94 34.94 34.94 34.94 34.94 41.30 41.30 41.30 41.30 41.30 41.30 39.75 39.75 39.75 39.75 39.73 39.75 8.23 8.23 190 Solidago graminifolia EP CH FF F DUO APM 80MB PE PE 90 10 0 0 0 1 5 95 3 0 0 0 0 0 100 0 0 0 0 O O 100 0 0 0 0 0 0 10 25 65 0 0 16 27 25 50 25 0 0 14 22 50 50 .0 5 1 6 34 83 15 0 16 0' 0 0 93 5 0 0 0 0 0 99 1 0 1 0 0 0 0 0 100 0 0 0 0 0 20 80 0 0 0 1 0 40 60 1 0 0 6 63 33 0 3 0 0 6 90 10 0 0 O O 0 100 0 0 0 0 0 0 0 0 100 0 0 0 0 0 0 100 0 0 0 2 0 5 95 1 0 0 0 10 60 30 5 0 0 2 60 40 O 0 0 0 0 80 20 0 5 O 0 0 DAY MONTH QQQOOOQOQOOOQ‘OQOOOOQQQ PCT FILL 8.23 8.23 8.23 8.23 15.90 15.90 15.90 15.90 15.90 15.90 51.57 51.57 51.57 51.57 51.57 51.37 40.18 40.18 40.18 40.18 40.18 40.18 .10 CLONE O O O O O O O O O O O O O O O O O O O O O O O O 0 000000.... bbbuuuuuuo-INNMNNNN“”her-”“h-NNNNNNNHHO‘Dfii-wfl Nanak’NDKDH3k)RINJNJIJKDKDAJNDKDkakak35383klh-rob-horouornuouorah-rotor- '95 ‘n w 0 N ouooouooooooouooooooooooooooooooooooooooooooooo 01 “ fl 0% 0980 191 Solidago lgpcea F BUD DAY MONTH CLONE FF F DUO DAY MONTH 0 100 23 7 3.2 0 5 95 29 7 0 100 29 7 3.2 0 35 65 4 8 o 100 4 a 3.2 15 85 0 9 8 40 60 9 8 3.2 50 50 0 13 8 100 o 13 s 3.2 80 20 0 18 8 100 o 19 a 3.2 90 10 0 22 8 90 0 22 8 3.3 0 0 100 23 7 o 100 23 7 3.3 0 0 100 29 7 O 100 29 7 3.3 0 10 90 4 8 o 100 4 a 3.3 5 95 0 9 8 o 100 9 a 3.3 10 90 0 13 8 60 4o 13 3 3.3 30 70 0 18 8 so so 13 a 3.3 25 75 0 22 8 so so 22 g 3.4 0 0 100 23 7 o 100 23 7 3.4 0 0 100 29 7 o 100 29 7 3.4 0 2O 80 4 8 o 100 4 a 3.4 0 60 40 9 8 as 15 9 3 3.4 5 70 25 13 8 100 o 13 a 3.4 10 90 0 18 8 100 o 23 a 3.4 40 60 0 22 8 30 o 22 g 5.0 O O 100 23 7 o 10o 23 7 5.0 0 O 100 29 7 0 100 29 7 5.0 0 10 90 4 8 o 100 4 a 5.0 0 55 45 9 8 so 20 9 9 5.0 10 90 O 13 8 100 o 23 3 5.0 30 70 0 18 8 100 o 23 8 5.0 85 15 0 22 8 go o 22 g 6.0 0 0 100 23 7 o 100 23 7 6.0 0 50 50 29 7 o goo 29 7 6.0 15 85 0 4 8 0 100 4 8 6.0 50 5O 0 9 8 35 15 9 a 6.0 60 4O 0 13 8 100 o 13 a 6.0 90 10 0 18 8 95 o 19 a 6.0 100 0 0 22 8 50 o 22 a 7.0 0 0 100 23 7 o 100 23 7 7.0 0 20 80 29 7 o 100 29 7 7.0 0 85 15 4 8 o 100 4 a 7.0 30 70 0 9 8 70 30 9 8 7.0 70 30 0 13 8 goo o 13 8 7.0 95 5 0 18 8 100 o 19 a 7.0 100 0 0 22 8 85 o 22 a 8.0 O O 100 23 7 o 100 23 7 8.0 0 0 100 29 7 35 35 29 7 8.0 0 70 30 4 8 75 25 4 3 8.0 50 50 0 9 8 95 o 9 a 8.0 50 50 0 13 8 60 4o 13 a 8.0 50 50 0 18 8 30 o 13 a 8.0 100 0 O 22 8 15 o 22 8 10.1 0 O 100 23 7 o 100 23 7 10.1 0 10 90 29 7 1992 Solidago Mean CLONE FF 9 nun DAY «our» CLONE FF r auo nov nourn 10.1 0 so so 4 a 12.2 30 70 o 9 a 10.1 80 20 o 9 a 12.2 50 so 0 13 a 10.1 so so 0 13 a 12.2 70 30 0 1a a 10.1 so 20 o 19 a 12.2 75 25 o 22 a 10.1 100 o 0 2 a 12.3 o 0 100 23 7 10.2 o 0 100 23 7 12.3 o o 100 29 7 10.2 o 0 100 29 7 12.3 o 0 100 4 a 10.2 o 20 so 4 a 12.3 0 2s 7s 9 a 10.2 0 so so 9 a 12.3 0 75 25 13 a 10.2 60 40 o 13 a 12.3 0 100 0 18 a 10.2 70 3o 0 1a a 12.3 85 15 0 22 a 10.2 75 25 o 22 a 12.4 0 0 100 23 7 10.3 o 0 100 23 7 12.4 o o 100 29 7 10.3 o 0 100 29 7 12.4 o 0 100 4 a 10.3 0 20 so 4 a 12.4 o 15 as 9 a 10.3 0 7s 25 9 a 12.4 0 10 90 13 a 10.3 35 as o 13 a 12.4 o 30 70 1a a 10.3 70 3o 0 1s 0 12-4 60 40 0 22 8 10.3 as 15 o 22 a 13.1 0 0 100 23 7 10.4 o o 100 23 7 13.1 o s 95 29 7 10.4 0 0 100 29 7 13.1 o 95 5 4 a 10.4 o o 100 4 a 13.1 10 90 o 9 s 10.4 0 30 7o 9 a 13.1 20 00 o 13 8 10.4 0 3o 70 13 a 13.1 75 25 0 1a a 10.4 0 9o 10 1a a 13.1 90 10 o 22 a 10.4 75 25 0 22 a 13.2 o o 100 23 7 10.5 o o 100 23 7 13.2 o 5 9s 29 7 10.5 o o 100 29 7 13.2 0 90 1o 4 a 10.5 0 0 100 4 a 13.2 15 05 o 9 a 10.5 o 40 so 9 a 13.2 30 7o 0 ~13 a 10.5 o 30 40 13 a 13.2 70 30 0 1a a 10.5 o 100 0 1a a 13.2 95 s o 22 a 10.5 50 50 0 22 a 13-3 0 100 23 7 11.0 o o 100 23 7 13.3 0 o 100 29 7 11.0 o 0 100 29 7 13.3 o o 100 4 a 11.0 0 65 3s 4 a 13.3 0 o 100 9 a 11.0 o 90 10 9 a 13.3 o 0 100 13 a 11.0 35 65 o 13 a 13.3 o 10 90 1a a 11.0 90 1o 0 1a a 13.3 0 85 15 22 a 11.0 90 10 0 22 a 13.4 o o 100 23 7 12.1 0 0 100 23 7 13.4 o o 100 29 7 12.1 o 35 65 29 7 13.4 o s 95 4 a 12.1 0 90 10 4 a 13.4 0 7o 30 9 a 12.1 20 so 0 9 a 13.4 0 100 0 13 a 12.1 45 55 o 13 a 13.4 5 95 0 1e 0 12.1 as 15 0 19 a 13.4 40 so 0 22 a 12.1 100 0 0 22 a 13.5 0 0 100 29 7 12.2 o o 100 23 7 13.5 0 0 100 4 8 12.2 0 so 40 29 7 13.5 o o 100 9 a 12.2 o 90 1o 4 0 13.5 o o 100 13 a CLONE 13.5 13.5 14.0 14.0 14.0 14.0 14.0 14.0 14.0 15.1 15.1 15.1 15.1 15.1 15.1 15.1 15.2 15.2 15.2 15.2 15.2 15.2 15.2 15.3 15.3 15.3 15.3 15.3 15.3 15.3 15.4 15.4 15.4 15.4 15.4 15.4 15.4 15.5 15.5 15.5 15.5 15.5 15.5 15.5 16.1 16.1 16.1 16.1 16.1 16.1 tlblkt ' <><>cn13¢5<>c><><><><><><>¢><><><><><><><><><>c><><><>¢><><><><><>¢><3<><>c><><><> 50 95 80 «DO 00 ”(all ”04 ”M 0 (noOOOOOOOOGOOOOOMUOOOOOOOO00000000000000 OUO 193 Solidaggrjuncea DAY HONTH 18 22 23 29 4 9 13 18 22 23 29 OOOOVVOOOQOVVOOOOOVVOOOOONVOOOOOVVOOOOOVVOOOOOV‘JOD CLONE 16.1 16.2 16.2 16.2 16.2 16.2 17.0 17.0 17.0 17.0 17.0 17.0 17.0 18.0 18.0 18.0 18.0 18.0 18.0 18.0 19.0 .19.0 19.0 19.0 19.0 19.0 19.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0 22.0 22.0 22.0 22.0 22.0 22.0 22.0 24.0 24.0 100 O- OOOUOOOOOOOOOOOO “M n O OOOUOOOO '00 OO O U IUD 100 100 100 100 50 100 100 100 100 DAY MONTH 22 23 29 4 9 22 23 29 VNOOOOONVOOOOOVVQOOOO\IVOOOOOVVOOOOOVVOOOOOVVOOOVVO CLONE 24.0 24.0 24.0 24.0 24.0 25.0 25.0 25.0 25.0 25.0 25.0 25.0 26.0 26.0 26.0 26.0 26.0 26.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 28.1 28.1 28.1 28.1 28.1 28.1 28.1 28.3 28.3 28.3 28.3 28.3 28.3 28.3 28.4 29.1 29.1 29.1 29.1 29.1 29.1 29.1 29.2 29.2 29.2 ~99 11 00000000000 has-- 000-.“ 0000000 0000000000000 100 100 194 Solidago juncea DAY NONTH OVVOOOOOVVNOOOOOVNCOOOONNOOOOONVOOOOVVOOOOQNVOOOOO CLONE 29.2 29.2 29.2 29.2 30.1 30.1 30.1 30.1 30.1 30.1 30.1 30.2 30.2 30.2 30.2 30.2 30.2 30.2 30.3 30.3 30.3 30.3 30.3 30.3 30.3 30.4 30.4 30.4 30.4 30.4 30.4 30.4 30.5 30.5 30.5 30.5 30.5 30.5 30.5 30.6 30.6 30.6 30.6 30.6 30.6 30.7 30.7 30.7 30.7 30.7 FF F 0 100 5 95 30 70 100 0 0 50 45 55 100 0 100 0 100 0 100 0 100 0 0 40 20' 80 70 30 100 0 100 0 100 0 100 0 0 40 25 75 70 30 100 0 100 0 100 0 95 5 0 15 10 -90 50 50 100 0 100 0 100 0 100 0 0 10 0 70 15 85 100 0 100 0 100 0 50 50 0 0 0 55 70 30 100 0 100 0 100 0 0 0 0 100 5 95 20 80 50 50 DUO 51' 000000000000 0 o- o. “0000000000000 640 on )0 ooooooooouoooooooooooooo DAY MONTH 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 OOOONOOOOOVOOOOOVVOOOOOVVOOOOGVVOOOOONVOOOOOVVOOOQ CLONE 32.1 32.1 32.1 32.1 32.1 32.1 32.1 32.2 32.2 32.2 32.2 32.2 32.2 32.2 32.3 32.3 32.3 32.3 32.3 32.3 32.3 32.4 32.4 32.4 32.4 32.4 32.4 32.4 32.5 32.5 32.5 32.5 32.5 32.5 32.5 33.1 33.1 33.1 33.1 33.1 33.1 33.1 33.3 33.3 33.3 33.3 33.3 .33.3 33.3 33.4 FF 15 75 100 100 100 100 40 DUO 60 0 0'. ”0 H 00 ‘4 u 00 "000000000000000000000000000000000000000 on 300002 195 Solidago jpncea DAY NONYN 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 VOOOOONV.OOOOVVOOOQDNVOOOOOVVOOOOOVVOOOOOVVOOOOOVV CLONE 33.4 33.4 33.4 33.4 33.4 33.4 33.5 33.5 33.5 33.5 33.5 33.5 33.5 34.0 34.0 34.0 34.0 34.0 34.0 34.0 35.0 35.0 35.0 35.0 35.0 35.0 35.0 36.0 36.0 36.0 36.0 36.0 36.0 36.0 37.0 37.0 37.0 37.0 37.0 37.0 37.0 38.0 38.0 38.0 38.0 38.0 38.0 38.0 39.0 39.0 a 14 on. 0“ "000000000 00 04 Out-0 0000000000000000000M0 ” 10 a... 0 000000000 100 100 O- HO'OQO u uoooououooooo 100 100 100 00000“ DUO 100 100 100 29 UN? NONTH 29 4 9 13 18 22 23 29 4 9 13 18 22 23 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 “VODQOONNOOOQONVOOOOO\IVOOOOOVVOOOQOVVOOOOONVOOQQOV CLONE 39.0 39.0 39.0 39.0 39.0 40.0 40.0 40.0 40.0 40.0 40.0 40.0 41.0 41.0 41.0 41.0 41.0 41.0 41.0 42.0 42.0 42.0 42.0 42.0 42.0 42.0 43.0 43.0 43.0 43.0 43.0 43.0 43.0 44.0 44.0 44.0 44.0 44.0 44.0 44.0 45.0 45.0 45.0 45.0 45.0 45.0 45.0 46.0 46.0 46.0 PF 50 100 100 100 on Oh. 0000000000 0040 UGO 100 100 IUD on 000000 DAY MONTH ONNOOOOONVOOOOOVVOOOOOVVOOOOOVVOOQOONVOOOOOVVOOOOO Solidqu jgpcea CLONE 46.0 46.0 46.0 46.0 47.1 47.1 47.1 47.1 .$.u.b.s.b.b:3 'u-u'u~u'u‘u . PF 60 100 100 40 50 80 100 40 50 80 100 .1. "‘ 80004 000000 000000 In!" ”I" 00000000000“ 00 0a 100 10 100 90 75 50 90 70 35 10 30 90 100 100 DAY NONTN 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 OOVNOOOOOVVOOOOONNOOOOOVVOOOOOVN°OQOOVVOOOOONHOOOO CLONE 51.1 51.1 51.1 51.2 51.2 51.2 51.2 51.2 51.2 51.2 52.0 52.0 52.0 52.0 52.0 52.0 52.0 54.1 54.1 54.1 54.1 54.1 54.1 54.1 54.2 54.2 54.2 54.2 54.2 54.2 54.2 55.1 55.1 55.1 55.1 55.1 55.1 55.1 55.2 55.2 55.2 55.2 55.2 55.2 55.2 55.3 55.3 55.3 55.3 55.3 FF 10 40 100 p 0000000000000000000000000000000 DUO on ‘30 0000000000 197 Solidago juncea OAY NONTH 13 18 22 23 29 00°\INOOOOOVNOOOOOVNOOOOOVVOOOOOVVGOOOOVVOOOOOVVOOO CLONE 55.3 55.3 55.4 55.4 55.4 55.4 55.4 55.4 55.4 55.5 55.5 55.5 55.5 55.5 55.5 55.5 ' 56.0 56.0 56.0 56.0 56.0 56.0 57.2 57.2 57.2 57.2 57.2 57.2 57.2 58.0 58.0 58.0 58.0 58.0 58.0 58.0 59.1 59.1 59.1 59.1 59.1 59.1 59.1 60.1 60.1 60.1 60.1 60.1 60.1 60.1 ‘ 0000000000000000000000000 'H hos-o 000” 000000 80 100 100 100 100 20 55 100 100 0000000 “ 8-0 0'0 00 on 000 000‘ mu 00000000004‘0000000000000 b 0000 100 DUO 10 100 100 100 100 100 100 100 100 100 100 100 50 100 100 100 70 40 10 100 O4 0 up» 000 000 0 0000 oooouoooooooooooooo OGY NONTH OOOOQV\IOOOOOVNOOOOOVVOOOOOVVOOOOVVOOOOOVNOOOQOVVQO CLONE 60.2 60.2 60.2 60.2 60.2 60.2 60.2 60.3 60.3 60.3 60.3 60.3 60.3 60.3 60.4 60.4 60.4 60.4 60.4 60.4 60.4 60.5 61.0 61.0 61.0 61.0 61.0 61.0 61.0 62.2 62.2 62.2 62.2 62.2 62.2 62.2 63.0 63.0 63.0 63.0 63.0 63.0 ~63.0 64.0 64.0 64.0 64.0 64.0 64.0 64.0 W1 19 00000000000000000000000000000000000000000000000000 100 p 0 0 on. 00 00000u00000 u 000 00“ 100 100 0010000 UN DUO 100 198 Solidqgg juncea DAY NONTH 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 13 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 4 9 13 18 22 OOOOONVOOOOOVV.O'CONNOOOOOVVOO0000‘!NOOOOONVOOOOOVN CLONE 65.1 65.1 65.1 65.1 65.1 65.1 65.1 65.2 65.2 65.2 65.2 65.2 65.2 65.2 65.3 65.3 65.3 65.3 , 65.3 65.3 65.3 66.0 66.0 66.0 66.0 66.0 66.0 67.1 67.1 67.1 67.1 67.1 67.1 67.1 67.2 67.2 67.2 67.2 67.2 67.2 67.2 67.3 67.3 67.3 67.3 67.3 67.3 67.3 67.4 67.4 FF 04 “00000088000000 0-0 V9- O- we 0000000000000 M ooooooooouoooooouoooooo DUO 100 100 100 20 0 0 0 100 100 100 50 5 0 0 100 100 100 25 100 100 100 95 70 100 100 100 95 60 100 . 100 OAT MONTH 23 29 4 9 13 18 22 23 29 4 9 13 18 22 23 29 VVOOOOOVVOOOOOVVQOOOOVVOGOOVVOOOOOVNODOOONVOOOOONN 199 Solidggoojgncea CLONE FF F BUD DAY NONTH CLONE FF F DUO OAT NONTH 67.4 0 0 100 4 8 69.0 0 100 0 13 8 67.4 0 0 100 9 8 69.0 30 70 0 18 8 67.4 0 30 70 13 8 69.0 100 0 0 22 8 67.4 0 95 5 18 8 72.1 0 0 100 23 7 67.4 60 40 0 22 8 72.1 0 0 100 29 7 67.5 0 0 100 23 7 72.1 0 0 100 4 8 67.5 0 0 100 29 7 72.1 0 0 100 9 8 67.5 0 0 100 4 8 72.1 0 0 100 13 8 67.5 0 0 100 9 8 72.1 0 0 100 18 8 67.5 0 40 60 13 8 72.1 0 25 75 22 8 67.5 0 80 20 18 8 72.2 0 0 100 23 7 67.5 30 70 0 22 8 72.2 0 0 100 29 7 68.1 0 0 100 23 7 72.2 0 0 100 4 8 68.1 0 0 100 29 7 72.2 0 0 100 9 8 68.1 0 0 100 4 8 72.2 0 0 100 13 8 68.1 0 5 95 9 8 72.2 0 0 100 18 8 68.1 0 90 10 13 8 72.2 0 25 75 22 8 68.1 0 100 0 18 8 73.1 0 35 65 23 7 68.1 100 0 0 22 8 73.1 10 90 0 29 7 68.2 0 0 100 23 7 73.1 35 65 0 4 8 68.2 0 0 100 29 7 73.1 90 10 0 9 8 68.2 0 0 100 4 8 73.1 100 0 0 13 8 68.2 0 0 100 9 8 73.1 100 0 0 18 8 68.2 0 5 95 13 8 73.1 100 0 0 , 22 8 68.2 0 0 100 18 8 73.2 0 20 80 23 7 68.2 0 5 95 22 8 73.2 10 90 0 29 7 68.3 0 0 100 23 7 73.2 35 65 0 4 8 68.3 0 0 100 29 7 73.2 65 35 0 9 8 68.3 0 0 100 4 8 73.2 100 0 0 13 8 68.3 0 0 100 9 8 73.2 100 0 0 18 8 68.3 0 0 100 13 8 73.2 100 0 0 22 8 68.3 0 85 15 18 8 73.3 0 5 95 23 7 68.4 0 0 100 23 7 73.3 0 70 30 29 7 68.4 0 0 100 29 7 73.3 15 85 0 4 8 68.4 0 0 100 4 8 73.3 50 50 0 9 8 68.4 0 0 100 9 8 73.3 90 10 0 13 8 68.4 0 0 100 13 8 73.3 100 0 0 18 8 68.4 0 85 15 18 8 73.3 100 0 0 22 8 68.4 100 0 0 22 8 73.4 0 10 90 23 7 68.5 0 0 100 23 7 73.4 0 75 25 29 7 68.5 0 0 100 29 7 73.4 10 90 0 4 8 68.5 0 0 100 4 8 73.4 65 35 0 9 8 68.5 0 0 100 9 8 73.4 95 5 0 13 8 68.5 0 0 100 13 8 73.4 100 0 0 18 8 68.5 0 0 100 18 8 73.4 100 0 0 22 8 68.5 0 90 10 22 8 73.5 0 15 85 23 7 69.0 0 0 100 23 7 73.5 0 70 30 29 7 69.0 0 0 100 29 7 73.5 20 80 0 4 8 69.0 0 0 100 4 8 73.5 85 15 0 9 8 69.0 0 95 5 9 8 73.5 100 0- 0 13 8 CLONE 73.5 73.5 73.6 73.6 73.6 73.6 73.6 73.6 73.6 74.0 74.0 74.0 74.0 74.0 74.0 74.0 75.0 75.0 75.0 75.0 75.0. 75.0 75.0 76.0 74.0. 76.1 76.1 76.1 76.1 76.1 76.1 76.2 76.2 76.2 76.2 76.4 76.4 76.4 76.4 76.5 76.5 76.5 76.5 77.0 77.0 77.0 77.0 77.0 77.0 77.0 FF 100 100 0000000000000000 on 0 0000000000000000000000000.00 100 100 100 200 Solidago jggpea DAY NONTH OOOOOVNOOOOOOOOOOOOOOODOOVVOODOONVOOOOO\IVOOOOQNNOO CLONE 78.1 78.1 78.1 78.1 78.1 78.1 78.1 78.2 78.2 78.2 78.2 78.2 78.2 78.2 78.4 78.4 78.4 78.4 78.4 78.4 78.4 79.1 79.1 79.1 79.1 79.1 79.1 79.1 79.2 79.2 79.2 79.2 79.2 79.2 79.2 79.3 79.3 79.3 79.3 79.3 79.3 79.3 79.4 79.4 79.4 79.4 79.4 79.4 79.4 79.5 w n H H 0 oooouooooouooooooooooooooooooooooooooo 4.. 088004 0000 ~41..- 0MM00000 100 100 DUO 100 100 100 100 DAY MONTH 23 29 4 9 13 18 22 23 29 6 “@0000VVOOOOOVVQOOQOVVOOOQOVVOQQOOVVOOOOOVVOOOOOVN CLONE 79.5 79.5 79.5 79.5 79.5 79.5 80.0 80.0 80.0 80.0 80.0 80.0 80.0 81.1 81.1 81.1 81.1 81.1 81.1 81.1 81.2 81.2 81.2 81.2 81.2 81.2 81.2 81.3 81.3 81.3 81.3 81.3 81.3 81.3 81.4 81.4 81.4 81.4 81.4 81.4 81.4 81.5 81.5 81.5 81.5 81.5 81.5 81.5 82.1 82.1 '91 n 0 000000000 00000000000000 100 100 50 BUD 100 100 201 Solidqgoljpncea DAY NONTH 29 4 9 13 18 22 23 29 VVOOOOOVVOOOOOVVOOOOOVVOOOOOVNOOOOONVOOOOONVOOQOOV CLONE 82.1 82.1 82.1 82.1 82.1 82.2 82.2 82.2 82.2 82.2 82.2 82.2 82.3 82.3 82.3 82.3 82.3 82.3 82.3 82.4 82.4 82.4 82.4 82.4 82.4 82.4 83.1 83.1 83.1 83.1 83.1 83.1 83.1 83.2 83.2 83.2 83.2 83.2 83.2 83.2 83.3 83.3 83.3 83.3 83.3 83.3 83.3 83.4 83.4 83.4 FF 30 65 100 100 0000000000000000000000000000000 80 100 UN 00 000000000008800000 100 100 100 100 80 100 100 100 100 100 25 50 100 100 100 100 100 50 40 100 100 100 ONT NONTN OVVOOOOOVVOOOOONVOOOQOVVOOOOONNOOOOOVNOOOOONVOOOOO CLONE 83.4 83.4 83.4 83.4 83.5 83.5 83.5 83.5 83.5 83.5 83.5 84.1 84.1 84.1 84.1 84.1 84.1 84.1 84.2 84.2 84.2 84.2 84.2 84.2 84.2 85.0 85.0 85.0 85.0 85.0 ' 85.0 85.0 86.1 86.1 86.1 86.1 86.1 86.1 86.1 86.2 86.2 86.2 86.2 86.2 86.2 86.2 86.3 86.3 86.3 86.3 ‘8‘ W ” 0 00000000000000000000000000000 on. 0 “It 00 0 0000 15 202 Solidqgg juncea F BUD DAY NONTH CLONE FF F DUO DAY NONTH 0 100 9 8 86.3 15 85 0 13 8 0 100 13 8 86.3 85 15 0 18 8 90 10 18 8 86.3 100 0 0 22 8 70 30 22 8 86.4 0 0 ’100 23 7 0 100 23 7 86.4 0 0 100 29 7 0 100 29 7 86.4 0 0 100 4 8 0 100 4 8 86.4 0 50 50 9 8 0 100 9 8 86.4 0 60 40 13 8 0 100 13 8 86.4 0 100 0 18 8 60 40 18 8 86.4 50 50 0 22 8 100 0 22 8 86.5 0 0 100 23 7 0 100 23 7 86.5 0 0 100 29 7 0 100 29 7 86.5 0 0 100 4 8 5 95 4 8 86.5 0 0 100 9 8 50 5O 9 8 86.5 0 30 70 13 8 90 10 13 8 86.5 0. 100 0 18 8 100 0 18 8 86.5 0 100 0 22 8 0 0 22 8 87.1 0 0 100 23 7 0 100 23 7 87.1 0 0 100 29 7 0 100 29 7 87.1 0 5 95 4 8 0 100 4 8 87.1 0 85 15 9 8 5 95 9 8 87.1 0 90 10 13 8 75 25 13 8 87.1 0 100 0 18 8 100 0 18 8 87.1 40 60 0 22 8 0 0 22 8 87.2 0 0 100 23 7 0 100 23 7 87.2 0 0 100 29 7 0 100 29 7 87.2 0 0 100 4 8 30 70 4 8 87.2 0 0 100 9 8 100 0 9 8 87.2 0 50 50 13 8 90 0 13 8 87.2 0 100 0 18 8 50 0 18 8 87.2 0 100 0 22 8 10 0 22 8 88.0 0 0 100 23 7 0 100 23 7 88.0 0 35 65 29 7 50 50 29 7 88.0 _ 0 85 15 4 8 75 25 4 8 88.0 20 80 0 9 8 65 0 9 8 88.0 85 15 0 13 8 60 0 13 8 88.0 95 5 0 18 8 50 0 18 8 88.0 100 0 0 22 8 20 0 22 8 89.0 0 0 100 23 7 0 100 23 7 89.0 0 0 100 29 7 15 85 29 7 89.0 0 10 90 4 8 90 10 4 8 89.0 0 85 15 9 8 90 0 9 8 89.0 0 100 0 13 8 85 0 13 8 89.0 5 95 0 18 8 85 0 18 8 89.0 100 0 0 22 8 5 0 22 8 90.1 0 0 100 23 7 0 100 23 7 90.1 0 0 100 29 7 30 70 29 7 90.1 0 0 100 4 8 100 0 4 8 90.1 0 35 65 9 8 85 0 9 8 90.1 0 80 20 13 8 CLONE 90.1 90.1 90.2 90.2 90.2 90.2 90.2 90.2 90.2 90.3 90.3 90.3 90.3 90.3 90.3 90.3 90.4 90.4 90.4 90.4 90.4 90.4 90.4 91.0 91.0 91.0 91.0 91.0 '94 ‘ 0000000000000000000000000000 100 100 100 70 30 100 100 100 203 Solidago lyncea DAY MONTH OOOVVOOOOOVVOOOOOVVOOQQOVVOO