inion 1293 01070 8166 | LIBRARY Michigan State University MSU LIBRARIES a — RETURNING MATERIALS: Place in book drop to remove this checkout from your record. FINES will be charged if book is returned after the date Stamped below. \S ma ND. VEE, The Hconomic Importance of Insects Hibernating in Rubbish, ~ gwae)o Mt t Contents. ; Pasre Introduction -------------------------- 3 Collections or lots -----~-------- ----- 4 . Hconomic importance of orders considered 16 Comparative list ------------ +22 see 17 Summary of orders --~------------------ 18 Observations -------------------------- LL summation -----------~-- = se ------ ~--- 25 / LOGTEGS THE ECONOMIC IMPORTANCE OF INSHCTS HIBiRNATING IN RUBBISicl. Willian T. Shaw. Introduction. The object of this investigation was to determine the numbers and tne economic importance of insects hibernating in neglected corners of tne farm, orchard, or garden as compared with the number of those nibernating in cleanly cultivated localities, and to ascer- tain the best time for and means of destroying injurious insects, should tney be found in such places. It has long been known that some of tne most troublesome insects pass tne winter as adults, ready to do injury imnediately upon the first sign of plant growtn. Where or in what numbers, perhaps, has not been so clearly understood By taking about tne same amount of material from various places around tne farm, garden and orchard, during the winter, and examin- ing it closely for insects, some very satisfectory results were Obteined and interesting observations made. The quantity of material taken in each case was as much as could be packed neatly in a vesi- cula, or collecting can used by botanists, or rousnly speaking about a peck. This would be, then, a very small proportion of tne litter sometimes found scattered over an acre of ground, and the number of insects in each lot would depend not upon a difference in the amount of material examined but upon the more or less favorable conditions offered for hibernating. a4 Considerable variation was noticed in the number of insects, where a series of collections was made from the same spot at various dates and different temperatures, and in early spring wnen the first warm days came, the numbers taken were micn less tnan in winter. Some points not tnougnt of at first developed as the search progressed and added interest to the work. For instance, certain kinds of leaves seemed more favorable for protection than otners. The number of insects varied with tne amount of moisture in the rubbisn, and like points which will be taken up more fully under subsequent neads. In all thirty-six collections were made, representing as far as practicable many different locations, proximity to different crops, and even spots remote from cultivation. About 1475 insects were collected, 277 of which are known to be injurious. Unless otherwise indicated, only adults were considered. Lot I, Feb. 8, 1900. Tem. 43° The material from which the insects found in Lot I were taken, was made up largely of hard maple leaves, a few oak, and leaves of the spruce, which were piled several inches deen. The location from which it was taken was shelt2red on two sides by a mixed spruce and maple hedge, with an exposure towards tne south east, presenting an ideal situation for insect hibernation. There was no snow on the ground, and the day was damp and rainy, tne leaves were without frost but very wet. Although much severe weather had been experienced previous to this date, the insects were apparently uninjured, and though sluggish, soon became active when brought into a warm room. Very few dead specimens were found. The leaves on account of tneir wet condition were quite closely held together, many being reflexed in such a way as to form a loop alongs -5- the midrib, into which tne insects had Crawled. The adjacent garden patcn had had a crop of asparagus on it the sumner before .« The old stocks had been taken off and tne ground was fairly clear of rubbish. There were no insects found among te spruce needles under tne hedge. The total number of insects found in tnis locality was 255. Note. Thysanura, sow-bufs, mites, spiders, larvae and punae were also found, as wes the case to a greater or less extent throughout all the collections made, Lot 2, Faéb. 9, 1900. Tem. 1&° Rubbish was taken from the soutn side of the same windbreak from which Lot I was sel:cted but tne material was collected fron among some gcoseberry bushes. [t was composed chiefly of maple leaves, wnich were piled tnick and deep and afforded good shelter. There were also a few pear and apple leaves. The location altnough more exposed tnan Lot I, was a very good sittation, being well pro- tected from tre north wind. There were many dead insects found here. The ground was ligntly covered witn snow. In all 73 insects were found, among which were tnose injurious to tne pear. . Lot 3, Feb. 12, 1900. Cloudy, Tem. 43° The leaves in tnis Lot were taken from und2r a »arberry hedge which extended between two fields, corn and meadow. The corn field had been kept perfectly clean, the previous year, am the meadow had peen mown tne summer vefore and now nad a sod of t~e ordinary ap- pearance for tne season. There was no grass under the hedge on the east side, next the cornfield, from wnich side the material was taken, consequently tne shelter was not good. The ground was free from snowe But 9 insects wefe found. -6- Lot 4, Feb. 12, 1900. Tem. 439 The spot from which the material in Lot 4 was taken was located near the soutn end of a deciduous woods. The leaves were taken from under a pile of oak branches whicn had retained their foliage, having been cut while in leaf during the previous summer. This appeared to be a good location. There was no snow on tne ground. The field which had buckwheat for its previous crop, was clean and had but very little rubbish left. Oak leaves and grass made up the bulk of tre material. A care- ful search showed more insects in the dead grass than in the oak leaves. The latter seemed to be rather harsh and unpliant to form good hibernating material. The total number of insects found was 30. Lot 5. Feb. 12, 1900. Tem. 43° This location was near Lot 4, but in the woods about four rods. The situation was not esnecially sheltered except by the forest trees, being in a space between tne large trunks. The material was chiefly made up of oak lexnves, with a few bass wood and maple among them. Those taken from the underside next the ground were much decayed, and were damp. No snow. The insects found numbered 45, Lot 6, Feb. 15, 1900. Tem. 17° The material was taken from a pile of wheat straw which lay at the edge of a buckwheat field. When the straw became thawed it was very wet, and was entirely free from insects. There was from four to five inches of snow on the ground. Lot 7. March 26, 1900. Tem. 40° The leaves forming the material taken were gathered from the south side of a clump of bushes on the campuse They were chiefly oa’ ~7- with spiraea, tulip tree, elm, and various kinds of leaves from shade trees and shrubs. The position was high, and appeared to be favorable for hibernation. Only 14 insects were found. Lot 8, March 28, 1900. Tem. 419 Stems of sweet clover which had been left piled in small heaps in a cleanly cultivated field were examined. The situation was an exposed one and the signs of insects were few. There was no snow. Only one insect was found, Lot 9, March 30, 1900. Tem. 379 This lot was also taken from an exposed spot in an open field, but where the land was not nearly so clean. A row of maple trees ran along the side of the field and consequently leaves from this tree and also a few from the oak were gatnered together ina patch of millet. The millet had not been cut the previous fall, and now the old stalks were standing about a foot high and somewnat scatter- ing, but thick enough to gather leaves and later snow which might be blown into them. The leaves where the sample was taken were pitied about a foot deep, and were on a slignt elevation which was rather dryer than the surrounding land which tnough wet was not submerged. The snow had just gone, but the frost was still in the ground . The insects found numbered 25. Lot 10. March 80, 1900. Tem. 37, Some grass with leaves of sycamore, elm, beech, and stems of scouring rush were taken from the low lands of a river bottom which were quite remote from a cultivated crop. High water had evidently covered the spot as the rubbish looked muddy, and was still quite damp. Otherwise the location was quite desirable, being on tne east ~8- side of a low tangled grassy thicket. Twenty insects were found. Lot 11. April 2, 1900. Tem 46° A well cultivated strawberry patch was selected from which to take the rubbish examined in this Lot. It was made up principally of the old leaves of the strawberry plants. The patch was free from grass and weed stalks. Nineteen insects were found, among which were insects injurious to the strawberry. Lot 12. April 2, 1900. Tem. 46? In this case the material which was made up of a few partially decayed clover stalks but chiefly of maple leaves, was taken from a timothy and clover meadow. The position was moderately exposed. There was no snow on the ground. Twenty-eight insects were found, Lot 13, April 2, 1900. Tem 46? In Lot 13 the vines and leaves were taken from a place where squashes had been grown the previous year. They were the leaves and vines of this plant, and were evenly scattered over the ground. In no case did they afford abundant protection, but were thick enough in places to make a network sufficient to collect the snow in winter. Twenty-two insects were found. Lot 14. April 3, 1900. Tem. 42° The grass and a few maple leaves which were collected tn this Lot were taken from the edge of a cleanly cultivated cornfield, near the posts of a wire fence. The position was not particularly shelter ed, but the dead grass was somewnat long and afforded fairly good shelter. -9- Principally Odeoptera were found, to the number of nine. Lot 15, April 3, 1900. Tem. 42° The material was taken from a field upon which beans had been grown the previous year. The cultivation had been fairly clean, a few weeds were showing. The rubbish consisted entirely of bean stocks which were piled in heaps. There was still some ice under the heaps and te position was exposed. The insects taken numbered 3l. Lot 16, April 3, 1900. Tem. 42° was The grass with a very few leaves which were taken,ycollected from a piece of sod in the center of a plum orchard which was cleanly cultivated. The grass was rather long and afforded fairiy good shelter. Twenty-eight were found. Lot 17, April 3, 1900. Tem. 40° This Lot was taken from the same place as that from which Lot 15 was taken, the object being to see if tne bean stocks, standing as they grew,- as tney were left in part of the field,- would harbor insects. If not it was thought it woula be better to leave the old stocks standi:.¢ rather than to pull them and leave them in heaps not burned. Some of the stocks were lying on the ground where they had been pressed by the weight of the snow. Here as in Lot 15, the insects found were very small and could find shelter where larger ones could not. Twenty-two were found here, and thirty-one in Lot 15. Lot 18, April 3, 1900. Tem. 380 The material was taken from the end of the field from which Lots 15 and 17 were taken to see what proportion of the insects, which might have been in the field, migrated to better shelter. The rubbish was taken from a copse on the river bank above high water mark, and was made up of grass from one spot, and leaves of apple or -10- thorn from another place a few paces distant. vrincipally Coleoptera wee’ found, numbering 42. Lot 19. April 3, 1900. Tem. 3° The rubbish was taken from the same spot as that from which Lot I was taken, the object being to determine if possible the time when the insects begin to leave their winter quarters. By this it is hoped to find the best time for spring burning. As nearly as possible the same amount and kind of material was taken in both in- stances. The result was that about fifty insects were found dead. The living ones found were quite inactive, and showed little signs of 1 leaving, except that they showed preference for the wet leaves and had quite deserted the dry leaves of tne top. The leaves were still too wet to burn. See also Lots 2? and 56. The insects found in this collection numbered 291. Lot 20. April 4, 1900. Tem 46° For this Lot the tops of mangolds were taken from piles where they had been left in the field which was cleanly cultivated. They were quite wet and partially decayed. There was ice in the bottom of the piles. The insects taken numbered 32. Lot 21. April 5, 1900. Tem. 48.2 Lot 21, was taken from the same place and was composed of the same material as Lot 6. It was taken to verify tne results found in Lot 6. There was still some frost in the pile. Only three insects were found, which would indicate that good, clean straw was not a favorable shelter. Lot 22. April 5, 1900. Tem. 48° Some oak leaves among which were leaves of elm and blue beech were taken from tne east side of a woods borderins an oat field. The location was fine and warm and had previously been well covered Lot 23, April 5, 1900. Tem. 53° Potato} tops were taken from a cleanly cultivated patch, where they had been left the previous atttumn. They were not in piles but were left scattered about as they had been dropped, consequently the shelt r which they afforded was not goode Forty-three insects were taken. -ll- with snow, traces of whicn still remained in tne fence corners. The "Bugs" found were very active. Pprobab}sy the Jassids were on the wing as few were found. The collection numbered 49 insects. Lot 22, April 5, 1900. Tem. 53.° Potatoe tops were taken from a cleanly cultivated patch, where they had been left the previous autumn. They were not in piles but were scattered about as they had been dropped, consequently the shelter which they afforded was not good. Forty-three insects were taken. Lot 24. April 5, 1900. Tem. 53° The north side of a clump of spruce trees was selected as the location from which leaves of oak, maple, elm and spruce were taken. The bulk of the leaves were oak. There was still some ice under the rubbish. Fifty-two insects were found. Lot 25. April 5, 1900. Tem. 53. The material for this Lot was taken from the north side of a plum orcnard. The land was in good condition and had no crop upon it. The rubbish taken consisted of leaves; oak, elm and a few beech. It was taken from the south side ofthe fence in a spot well exposed to the sun. Twenty-two insects were found. 26 Lote 26. April 7, 1900. Tem 50° Material composed almost entirely of oak leaves was taken from a clump of lilac bushes on the campus, from a spot where the grass had been mowed and kept short the previous year. The location was fairly well protected and was well covered with snow during February and March. The leaves were dry almost to the ground, and few insects were found. This was the date upon which the leaves were being raked upon lawns for the purpose of burning. Only six insects were found. -12- Lot 27. April 7, 1900. Tem. 50° For this Lot tne same material was taken, and the same locality chosen as in tne case of Lot 1 and 19 and later 36. The material was partly dried and a heap of it was raked together and burned. It did not burn readily but by frequent stirring it was finally burned completely. A sample was examined for insects. Those found were all active. Jassids and lacewinss were seen flying about. Sowbé@gs, millipeds and angle-worms were numerous, tne latter no doutt having come up from the ground. The insects wtill reinaining in the leaves numbered 116, showing a marked decrease. Lot 28. April 7, 1900. Tem. 67° Lot 28 was taken from the same place as was lot 2. The leaves were now dry almost to tne bottom of the layers. But thirty-three insects were found, showing a decrease here also. Lot 29. April 7, 1900. Tem 67° The material, chiefly hard maple leaves, similar to that in Lot 2, was taken from under some current bushes about ten feet from the hedge near Lot 2. The leaves were dry excepting those near the ground which were still quite wet. Twenty-four insects were found. Lot 30. April 7, 1900. Tem. 70% Some maple leaves were taken from the roots of blackberry bushes. They had been flooded during the winter and were covered with sediment, but were now partly dry. Only three insects were found. Lot 31. April 7, 1900. Tem. 68° Apple and hard maple leaves were taken from an old apple archard grown over with sod. The leaves were partly dry and were piled deep petween the tussocks of grass. But eleven insects were found. -13- -Lot 32. April 7, 1900. Tem. 57¢ The material was taken from tne sane orchard, but fron a part of it where the orchard was cultivated. The rubbish was made up purely of apple leaves, which do not seem to be suitable as material for hibernating as tney lie so flat when wet and are so hard and un- bending. Leaves were wet in the lower layers onity. Twelve insects were found. Lot 33. April 9, 1900. Tem. 43° Some oak leaves were taken from a pile of rubbish which had been raked up and left standing for about two days. The object of taking this Lot was to ascertain if insects remained in tne rubbish after it had been raked upe Only four insects were found which would sug- gest that tney had deserted the disturbed leaves. Lot 34. April 10. 1900. Tem. 40° Tne material in this lot was made up of leaves from tne pine and spruce, and was taken from the nortn side of a clump of these trees. There was also a little dead grass mixed in witn tne leaves. Evergreen leaves do not afford good shelter for insects, appar- ently, as thergwas not a sign of an insect in the material examined. Lot 35. April 10, 1900. Tem. 40. In tnis case the material was taken from the compost heap, and was composed of leuves, chiefly oak, which were taken from the campus two days before. It was thougnt that tne insects misnt be smothered by being buried in tne heap, but no dead ones were found. Hleven insects were taken. Lot 36. November 24, 1900. Tem. 32°? Material was taken from the same place as Lots 1, 19 and 27. There had been some cold weather with about four inches of snow a week or so before this, sufficient cold to drive the insects to shelter. -14- The summer's crop was asparamus again. The collection was nude to ascertain the proper time to burn as the leaves were sufficiently dry at this time. Providing the insects had taken shelter for the winter this plan of destroying insects mignt be practical. The results showed a total of 104, many of which were injurious Heteroptera and Homoptera. All were sluggish. HBconomic Importance of tne Orders Under Consideration. _ The first order considered is tne Order Orthoptera to which belong the grasshoppers, crickets and cockroaches, very many of which are injurious. As will be noticed, not many of these insects were found. The two following orders Heteroptera and Howcotera contain in- sects commonly known as "Bugs", most of which are very injurious especially to young and growing vegetation from which they suck tne Sape On account of this habit of piercing t:e tissues of the plants aid obtaining their food from below the surface, trey are difficult to control, avoiding as trey do the poisens of the spray pump, and being killed only by some form of contact spray as kerosene or to- bacco. To these orders belong tne Chinch-buc, Tarnished Plant-bug, Jassids and Psylla,. The Neuroptera contains chiefly beneficial insects as Aphis- liens (Chrysopa), insects which do much good by killing plant-lice. The Lepidoptera, the order to which belong tne Butterflies and Moths althougn containing adult insects of great beauty, contains .- forms whicn are very destruc tive in the young or larval stage. Diptera or two winged insects, flie 8, contain very serious enemies although some as the Syrphus flies are very beneficial as their larvae feed pargely on plant lice. Others are important as scavengerSe -15- Among the Coleoptera or Beetles are found both forms, beneficial and injurious. Of the former the Carabidae or Ground-beetles, tre Staphylinidae or Rcve-beetl:s are important as destrcyers of other insects. The Coccinellid:e or Jady-bug family like the Aphis-lions are very destructive to the plant lice. Of tre latter, many such as those belonging to tne families Chrysomelidae, Scar: baeida: and Elat eridae are destructive to vegetation. Of the Order Hymeno;tera much good may be said. Here are found such families as Cralcididae, Ichneumonida:, Proctctrnupidae and Brachonidae, containing little wasp-like insects which destroy great numbers of larvae destructive to crops. List Showing the Relative Number of Insects Hib:rnating in Good and Poor Localities. Poor. Goode Lot 3 9 insects : Lot 1 255 insects " 64 30 " : " 2 73 " " 6 0 " : " 6 65 45 " " 8 1 " : 7 14 " " 10 . 20 JM : " 9 25 " "11 19 " : " 16 28 " " 12 28 " : * 18 42 " "13 Le " : " 19 291 " "14 9 " : " 22 49 " " 15 31 " : "27 116 n "17 22 " : " 28 33 n * 20 32 " $ " 29 24 " " 21 3 " : " 31 11 " "25 43 " : n 36 104 " " 24 52 " “ 25 La " a 26 6 " | 30 3 " 0 32 12 " 0 54 O 0 Total 364 insects. Total 1109 insects. -16- SUMMARY OF ORDERS, FAMILINS, BTC. Orthoptera, Blattidae, Pyconoscelus (?) <7. Acrididae, Chortophaga (f), (§) 7: Tettigidea, +. iq. Tettix, §,. Heteroptera, Reduviidae, ($) = Nabidae, 7 a a Coriscus (%) Fg Fy ia 18 ig ty as’ $3! 3 Tingitidae, Piesna (+) cinerea,$.2,./,. Acanthiidae Triphleps (?) (%) % Capsidae, Lygus (f) pratensis, 4,4. Lygaeidae, Cymus (?) #. Peliopelta, 2. Peritrechus, 4, Trapezonotus, 4. Coreidae, Corizus, =.2,4,4,,2. Pentatomidae, GON a Brochymena ({) 4-pustulata, 4° 3’ 29° Ruchistus (+) ictericus, 4, Euchistus ({) tristigmus +. Peribalus limbolarius, >. 4,° ww Is & { . ~ “SIS ‘9 N "| » “~ » N &| a fof /,3,4 , ,z , “lis 77'S 260 Zu 2F Homoptera 2 Jassidae (§), 3° 7a Se - + 2e,$ ,£ 0-3 2 , yphlocyba (+) comes ¥%- 4’ 77’ %4' 2" 47" 33° 36 Obliqua +4, +4,- querci 4-4--4,- 7 te, t r ~ on tricincta ; ig’ Ay’ 4733’ 36 BD e Z Agallia (fF) 4-punctata ( ),%,- Sanguinolenta,;.5.2.5.+%3 Psyllidae, _— 4 Livia vernalis, i, Psylld (+t) pyricola, = Psylla (4) 4-lineata,%,4. 3% 3,-= Trioza (f) 3y. Aphididae (1), (S), %- 44 -17- Neuroptera, Chrysopidae, Chrysopa plcrabunda (x), &- +, 2 thy Ge Se Hemerobiidae, Micromus posticus (x*)?t,32,,.3%,- Lepideptenra, Noctuidae, Monestra trifolia, 3,- Scopelosoma (4), 3, Diptera, Tipulidae Pde Cecidomyiidae (+), 3,- Phoridae, Phora, 3+ 3: 79° By" 28° 56 . Muscidacs $44. iy ig dy ba' a0" Be 3G Coleoptera, Carabidae, Agonoderus (fT), "% "29 a, Bembidium (f), 2.4 Het ba dy ken ae 5 Blechrus (HK) , Bey: 4, SE ig Bradycellus rte: Dyschirius (3%) +. Platynus 09 gt Pterostichus (*),4°4%° 27° % Stenolopnus Aya tg EL. Tachy 3 (x<) Tetragonodert as (9K) ye Rydrophilidae, Cercyon, <, Silphidae, Clambus, £ Pselaphidae, Ctenistes, Stapny tint aae Actobi WK - ) le Alerooharint | (trive) (*) $ £. Falagra (* 7B 2 Homalota (3¢) , 4 , aare 7, bh ie’ Gy’ wy Lathrobiun (3) ay Mycetoporus ( (xe) ,% Oxytelus (*) , 4,8, Paederis (x) ys Scopaeus (*),7°% 4° % 5 Stilicus (X) 13s Sunius, (%*),i- 45" fy p ar Le Tachyporus (3) _4 J Xantholinus ose a 10 Wag’ 22° 29 7 QM a ar 27 (26 2S 47° 36 -18- Trichopterygidae, Ptenidium, 3.- . Trichopteryx, % ‘32° Phalacridae, Litochrus, 4. Olibrus,2.45.5,-4.'4,¢ 4.4. Phalacrus, aos . 60 7 Corylophidae, ‘* “” 3% Corylophus truncatus, +. Orthoperus, 4, . +, Sericoderus, +) Coccinellidae, Coccinella (*) H+ 43° 32 Hippodamia (*), “ Psyllobora (x), Scymnus (XX), 2. Cryptophagidae, ' Tomarus y +¢- Mycetophagidae, Litargus, +. Dermestidae, | Anthrenus (}), iq: zy Nitidulidae, Buparia, 4. jf.) ig: Nitidula, |.: Trogostidae, Nemosuma, 4 Lathridiidaa, ; , 6 ; . : Fa pie! bie Gy he tet OL 8 eae Daseyliidas, DEE TAF 3 iene ER ay Cyphon (Meet a 7 vy 47 Jo Blateridae, ss” Cryptothypyis (4) obliquatulus 29° ocarabacidae, Aphodius (f), 4.4.2.4 2. Chrysomelidae, eS Crepidodera (fT) atriventris,;.+ Crepidodera (ft) sp.,1, Glyptina cerina, +. Paria (fT) 4-notata,+.g 2. Phyllotreta (4),%, u Paylliodes (4) punctulata,s,. ed N G a'r q' 27°30" Tad a, 4 a ’ ak rf Js IR B57 4: & Tenebrionidae, Paratenetus, + Anthicidae, Anthicus @.4°%.2,¥,6¢ 1.2. 4 .2,5,6,7,4 + , 3 FW Te 1S 1g tn 17" 1" ig! RO Re ee’ zs > z + = Notoxus, 1 nes 7 24 49~" 2° 5, Curculionidae, OW 8 aa a ap ag dg 3, SE, Smicronyx, +. Scolytidae, Hylesinus (+), i,- “*% ~19- Hymenoptera, Ichneumonidae, Pezomachus (*) 5, - Pterocomus (7) (x) +. Braconidae, 7 Ganychorus (*), 2 | Chalcididae, Merisus (ve) ;. Proctotrupidae Paramesius (©), fq: Zz: Polygnathus (7), Ge), 4.. Thoron (?) (*) (8) "=. Myrmicidae, Cremastogaster (7), :. (?) Identification doubtful. (%*) Beneficial. (+) Injurious. (S) Immature. Note. The fraction to the right of the genus or species is meant to represent the number of specimens found and the locality in which they were taken, the numerator or upper figure referring to the number of insects and the denominator the locality for example, Lygus pratensis 4/1, would mean that four insects of this kind were collect- ed from Lot I. ~20- Observations. It may be of interest to note the relative number of insects found classified as injurious, beneficial am indifferent. Twenty- seven per cent of the insects collected are known to belong to in- jurious genera. Nineteen per cent are known to be beneficial, while the remainder, fifty-four per cent are indifferent. Forty-eight per cent of tne injurious insects were Heteroptera and Homoptera in- sects known to be very injurious and as previously explained hard to check by artificial means. Of these seventy-five per cent were found hibernating in places of best shelter, seeming to avoid clean, open localities, a fact which should be significant. In estimating these percentages only those genera known to be injurious were considered with the exception of the Diptera or flies in which the family Phoridae was reg: rded as indifferent, the fami- lies Ceci..omylidae, and Tipulidae as injurious and the Muscidae on account of the injurious and beneficial members contained, and for the reason that they were not traced to genera were not considered in reckoning the percentages. In the beneficial list were included all the Neuroptera or Aphis lions, all the Hymenopter or Wasps but the Ants, all the Staphylinidae or Roveobeetles, all the Coceinellidae Or Tady-bug, and all the Carabidae or Ground-beetles, except those genera known to be injurious. These percentages might be considered as average inasmuch as the previous summer was not marked by anyje 8- pecial outbrake of insects in the locality from which the collections were made, Some of the more common-insdécts found were:- Tarnished Plant-bug (Lygus pratensis). Spittle insects (Agallia). Jassids (Typhjocyba). Psylla, (Psylla) Bewiibium, and Corticario. The last named genus al- though very common is represented by small insects which probably are never very injuriouse -2]- By a careful examination of the list snowinz the rejative num- ver of insects hibernating in good and poor locations it will be seen that in almost every case where the conditions had been left more favorable, there the greatest number of insects were found. In the majority of cases in the list representing tne localities with the least insects neat farming had been practical the year before. It was found tnat sone materials were more favorable fcr hiber- natination than others. Hard maple leaves appeared to be among the best and wherever they were found the number of insects was greater See Lot 12. Apple and oak leaves were poor, probably on account of their being hard and unpliant, while the maple either crumpled or folded in such a way as to form small openings into which the insects crawled. See also Lots 4 and Sc. The leaves of spruce were almost destitute of insects as was also the wheat straw examined, & fact which shows the importance of using good, clean straw rather than leaves as a covering for strawberries or other plants needing protec- tion in the winter. See Lots 6 and 2l. In regard to the time at which the insects began to leave winter quarters it might be best shown by an examination of Lots l 19, 27 and 36 which in brief is this:- as the weather became warm and the topmost leaves dry, the insects began to leave, even before the rubbish was dry enough to burn well. Few insects were found wher the leaves were dry, and those insects which fly readily as Jassids and many of the "Bugs", which are usually injurious left the rubbish soon after the warm days arrived. This was also true of the Lacewing:; which are beneficial insects. [It would seem from this that spring burning would not be completely successful when we attempted to destroy noxious insects’. On the other hand by examining Lot 36 it will be seen that sufficient cold weather and low temperature -22- existed to drive insects to winter quarters. jo \W Already Heteroptera and Homoptera,- generally injurious- were found in numbers and were sufficiently sluggish to render their de- struction by fire successful. As stated in Lot 36 snow had fallen previously but had melted am the leaves had been dried by frost and wind until they were in good condition for burning. Indeed there were times when burning could have teen done for several days following. It was noticed in the spring that the insects left their winter quarters after the leaves were raked up, the temperature being higher and the insects more active, they were enabled in many instances to fly on being disturbed. See Lot 33. Special attention was given to the searching for insects known to be troublesome on certain plants. Ina few cases insects were found near the plant upon which they had fed, for example, Pear Psylla Paria a genus containing enemies of the strawberry, and Jassids of the oak. In direct contradiction to this was an instance (Lot 5) where Paria was found well in the woods, certainly remote from the tame strawberry plants at least. In locations where this insect is troublesome it might be well to choose for strawberries, a field remote from the woods. As many insects were found in the harvested fields the import- ance of fall plowing would be evident, turning under completely all stubble or weeds which serve to harbor insects in whatever form they might pass the winter. That insects seek shelter in the fall and choose protected spots is shown in Lots 15, 17 and 18 where the number in Lot 18, the most sheltered spot, is much larger than in the other Lots. In Lot 7 although the location was good, the scarcity of insects might be accounted for by the fact that the surroundings had been -23- kept especially neat and no field crop had been near bye A very marked decrease was shown in the number of insects found in Lots 19 and 27, the leaves being dryer andthe weather warmer on the date of the latter collection. Summation. First. It is important that all rubbish be raked out of cor- ners and burned at the proper time, and that fence and hedge rows be kept neat as a means against injurious insects. Second. As shown by a study of the activity of the insects during different temperatures it is important that burning should be done on cold days. As an illustration for this see Lot 27 and 356 where the temperatures were respectively 50° and 32° Third. Burning in fate fall and during winter would seem preferable to spring burning. Fourth. FaVl plowing would be recommended as means of destroy- ing insects and getting rid of their winter protection, Fifth. As is shown by an examination of Lots 6 and él, the use of good clem straw is preferable to the use of leaves when employ ed as a covering or protection for tender plants and shrubs, Sixth. As insects were found wintering near the trees or plants upon which they had fed during summer it is important that extreme care be taken to burn all the rubbish found in the neighbor- hood of vegetation to be protected or freed from insect attack. -18- Trichopterygidae, Ptenidiuum, 4.- Trichopteryx, $-'32' 37° Phalacridae, Litochrus, 4 Olibrus,?.4.5..4 ;4,6 4.4. Phalacrus, ot . 0 27 Corylophidae, ‘ “7 3% Corylophus truncatus, 5. Orthoperus, 4, . 5, Sericoderus, +. Coccinellidae, Coccinella (x) i! 33 ‘ oh Hippodamia (%*), <. Psyllobora (*),«: Scymnus (*),2. ’ Cryptophagidae, ' Tomarus, +4 Mycetophagidae, Litarsus, +. Dermestidae, Anthrenus (+), i9* a4: Nitidulidae, Buparia, 4. jo: th. Nitidula, 7.5.5, .27 Trogostidae, Nemosoma, 4_ Lathridiidaa, Corticaria (+), *- gin 4 rin aa Cyphon (PQ) Fae e en Blateridae, “_” Cryptorthypyis (4) Oobliquatulus 29° Scarabaeidae, Aphodius (fF), tet ott yb Chrysomelidae, se aa” Crepidodera (f) atriventris,;.+, Crepidodera (ft) sp.,1+, Glyptina cerina, ‘. Paria (f) 4-notata,+.¢. 2. Phyllotreta (+),%, " Paylliodes (4) punctulata yte,: Tenebrionidae, vs Paratenetus, + Anthicidae, Anthicus %.4°3-4,8,8 2. ¥ 2,56 Notoxus, ‘#8... , Oy wan Curculionidae,’ *~’¥"7'7 4% wy 5, %, 66 SmicronyxX, +. scolytidae, Hylesinus (+), i. 6 ‘ ‘ . : T' 7 10 te 13" Wy! Gee! Dascyllidae iz , 12 ,3 9 =e tt , Aq’ 2y' 29' Zo f sO 07, le! 17'78 2 4 pt f as JR as-' J: £ 39,2 ,12,2 ‘P20 2M ay Ay’ 2 Lf z Y d- aR! FD 2 Rk -19— Hymenoptera, Ichneumonidae, Pezomachus (*) 3. - Pterocomus (7) (*) +, Braconidae, / Ganychorus (*) F- Chalcididae, Merisus We) ;- Proctotrupidae Paramesius () tq 24: Polygnathus (2), G&), 4.. Thoron (?) (*) (8)'5 Myrmicidae, Cremastogaster (?),°:. (?) Identification doubtful. (<) Beneficial. (¢) Injurious. (S) Immature. Note. The fraction to the right of the genus or species is meant to represent the number of specimens found and the locality in which they were taken, the numerator or upper figure referring to the number of insects and the denominator the locality for example, Lygus pratensis 4/1, would mean that four insects of this kind were collect- ed from Lot I. ~20- Observations. It may be of interest to note tne relative number of insects found classified as injurious, beneficial am indifferent. Twenty- seven per cent of tne insects collected are known to belong to in- jurious genera. Nineteen per cent are known to be beneficial, while the remainder, fifty-four per cent are indifferent. Forty-eight per cent of tne injurious insects were Heteroptera and Homoptera in- sects known to be very injurious and as previously explained hard tc check by artificial means. Of these peventy-five per cent were found hibernating in places of best srelter, seeming to avoid clean, open localities, a fact which should be significant. In estimating these percentages only those genera known to be injurious were considered with the exception of the Diptera or flies in which the family Phoridae was reg: rded as indifferent, tne fami- lies Ceci..omylidae, and Tipulidae as injurious and the Muscidae on account of the injurious and beneficial members contained, and for the reason that they were not traced to genera were not considered in reckoning the percentages. In the beneficial list were included all the Neuroptera or Aphis lions, all the Hymenopter or Wasps but the Ants, all the Staphylinidae or Roveobeetles, all the Coceinellidae or Tady-bug, and all the Carabidae or Ground-beetles, except those genera known to be injurious. These percentages might be considered as average inasmuch as the previous summer was not marked by anyes— pecial outbrake of insects in the locality from which the collections were made, Some of the more common-insécts found were:- Tarnished Plant-bug (Lygus pratensis). Spittle insects (Agallia). Jassids (Typhjocyba). Psylla, (Psylla) Bendibium, and Corticario. The last named genus al- though very common is represented by small insects wnich probably are never very injurious.e -2)- By a careful examination of the list snowing the rejative num- ver of insects hibernating in good and poor locations it will be seen that in almost every case where the conditions had been left more favorable, there the greatest number of insects were found. In the majority of cases in the list representing the localities with the least insects neat farming had been practical the year before. It was found that sone materials were more favorable fcr niber- natination than others. Hard maple leaves appeared to be among the best and wherever tney were found the number of insects was greater See Lot 12. Apple and oak leaves were poor, probably on account of their being hard and unpliant, while the maple either crumpled or folded in such a way as to form small openings into which the insects crawled. See also Lots 4 and Sc. The leaves of sprtice were almost destitute of insects as was also the wheat straw examined , & fact which shows the importance of using good, clean straw rather than leaves as a covering for strawberries or other plants needing protec- tion in the winter. See Lots 6 and 21. In regard to the time at which the insects began to leave winter quarters it might be best shown by an examination of Lots l 19, 27 and 36 which in brief is this:- as the weather became warm and the topmost leaves dry, the insects began to leave, even before the rubbish was dry enough to burn well. Few insects were found wher the leaves were dry, and those insects which fly readily as Jassids and many of the "Bugs", which are usually injurious left the rubbish soon after the warm days arrived. This was also true of the Lace ying: which are beneficial insects. [It would seem from this that spring burning would not be completely successful when we attempted to destroy noxious insects, On the other hand by examining Lot 36 it will be seen that sufficient cold weather and low temperature -~22- existed to drive insects to winter quarters. ‘fo \¥ Already Heteroptera and Homoptera,- generally injurious- were found in numbers and were sufficiently sluggish to render their de- struction by fire successful. As stated in Lot 36 snow had fallen previously but had melted and the leaves had been dried by frost and wind until they were in good condition for burning. Indeed there were times when burning could have teen done for several days following. It was noticed in the spring that the insects left their winter quarters after the leaves were raked up, the temperature being higher and the insects more active, they were enabled in many instances to fly on being disturbed. See Lot 33. Special attention was given to the searching for insects known to be troublesome on certain plants. Ina few cases insects were found near the plant upon which they had fed, for example, Pear Psylla Paria a genus containing enemies of the strawberry, and Jassids of the oak. In direct contradiction to this was an instance (Lot 5) wnere Paria was found well in the woods, certainly remote from the tame strawberry plants at least. In locations where this insect is troublesome it might be well to choose for strawberries, a field remote from the woods. As many insects were found in the harvested fields the import- ance of fall plowing would be evident, turning under completely all stubble or weeds which serve to harbor insects in whatever form they might pass the winter. That insects seek shelter in the fall and choose protected spots is shown in Lots 15, 17 and 18 where the number in Lot 18, the most Sheltered spot, is much larger than in the other Lots. In Lot 7 although the location was good, the scarcity of insects might be accounted for by the fact that the surroundings had been -23- kept especially neat and no field crop had been near bye A very marked decrease was shown in the number of insects found in Lots 19 and 27, the leaves being dryer andthe weather warmer on the date of the latter collection. Summation. Firste It is important that all rubbish be raked out of cor- ners and burned at the proper time, and that fence and hedge rows be kept neat as a means against injurious insects. Second. As shown by a study of the activity of the insects during different temperatures it is important that burning should be done on cold days. As an illustration for this see Lot 27 and 36 where the temperatures were respectively 50° and 32° Third. Burning in fate fall and during winter would seem preferable to spring burning. Fourth. FayVl plowing would be recommended as means of destroy- ing insects and getting rid of their winter protection. Fifth. As is shown by an examination of Lots 6 and 2l, the use Of good clem straw is preferable to the use of leaves when employ ed as a covering or protection for tender plants am shrubs, sixth. As insects were found wintering near the trees or plants upon which they had fed during summer it is important that extreme care be taken to burn all the rubbish found in the neighbor- hood of vegetation to be protected or freed from insect attack. A rome hy “TG STATE UNIV. HL LIBRARIE In iI