A 3mm 0!: man-eons 5cm mxme sea-n. 5AMF‘LES. mom fizwggam' PLANTAf’KG-RS Timsts €09 Hm Degree of M. 3. MECHEGAN STATE UMVERSETY Robert J? Van. Kmampembem 1965 LIBRARY MichiganSuw U' . J fiESl: A STUDY OF METHODS FOR TAKING SOIL SAMPLES FROM BLUEBERRY PLANTATIONS By Robert J. Van Klompenberg AN ABSTRACT OF A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Soil Science I965 ABSTRACT A STUDY OF METHODS FOR TAKING SOIL SAMPLES FROM BLUEBERRY PLANTATIONS by Robert J. Van Kompenberg A study was undertaken to determine how to effectively secure a composite soil sample that would reflect the fertility level of the soil from a blueberry plantation. To test the sampling methods replicated soil samples were obtained and soil tests were made. Soil tesusresults from several replications were compared on the basis of the following limits of acceptability: pH i 0.2 of a unit P i 7.0 pounds per acre K _;RIO.0 pounds per acre Ca 1 25.0 pounds per acre Mg : 30.0 pounds per acre Soil test results that fell outside these limits were classed as not acceptable. In order to obtain a close relationship between.the replicates, it was necessary to consider the placement of the fertilizer. Consequently, soil samples were taken within the fertilized area, and most of the soil test from replicated samples within this area fell within the acceptable range. The most reproducable results were obtained from composited soil samples that contained 20 or more subsamples. A procedure for taking soil samples from a blueberry plantation was deveIOped. It recognized differences in soils, methods of fertilization, and number of subsamples per composite for a given area. The method was tested at seven locations and under four different methods of fertilizer placement. The data indicated that only l4 soil tests out of a total of l35 fell outside the range of acceptability. Of these, only five were significantly out of the acceptable range. This study suggests that reliable soil samples from blueberry plantations can be obtained with the following provisions: l) samples must be taken to a depth of 8 inches; 2) a composite sample must contain 20 or more sub- samples from the area of fertilizer application; 3) the sampling must be restricted to one soil condition of not more than l0 acres in size. A STUDY OF METHODS FOR TAKING SOIL SAMPLES FROM BLUEBERRY PLANTATIONS By Robert J. Van Klompenberg A THESIS Submitted to _. Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Soil Science I965 ACKNOWLEDGMENTS The author expresses his sincere gratitude to the members of the Soil Science Department for their helpful suggestions in this investigation. .Special appreciation is directed to Dr. L. S. Robertson for his guidance, timely assistance, and words of wisdom throughout this study. He is also indebted to Dr. J. Shickluna for his helpful suggestions and encouragement. The writer is grateful to Prof. H. Wassink and other growers of blueberries for their cooperation 'and for the information that they supplied on past management practices. The c00peration of the State Soil Testing Laboratory is gratefully acknowledged. TABLE OF CONTENTS I. Introduction. 2. Review of Literature. a) b) C) d) e) f) 9) Origin of cultivated blueberries Soils used for blueberry culture . Soil pH requirements for blueberries Soil fertility levels and balance. Fertilizer recommendations Soil testing . Soil sampling. 3. Procedure . a) b) C) d) e) 1‘) Considerations in soil sampling in blueberry plantations. . . Methods of sampling soils. Chemical tests on soil samples Estimations of soil variability. Estimations of effect of fertilizer on soil test results. . Devel0pment of acceptable soil sampling procedures.. . . . . . . . . . . . h. Results and Discussion. a) Acceptable results of repeat soil tests. b) Soil fertility variation in a blueberry C) plantation.. Determining the best number of subsamples per composite. Page mommrt-www lO IO ll ll l3 l3 l4 l8 Table of Contents, cont. Page d) The effect of fertilizer placement on -soil test results - . ... . . . . . . . . 22 e) Reproducibility of soil test results from samples taken in plantation . . . . . . . 29 f) Final testing of the proposed sampling method . . . . . . . . . . . . . . . . 38 5. Summary . . . . . . . . . . . . . . . . . . . . . Ah 6. General Discussion . . . . . . . . . . . . . . . 46 7. Literature Cited. . . . . . . . . . . . . . . . . A9 8. Appendix. . . . . . . . . . . . . . . . . . . . . 54 a) Saugatuck Series . . . . . . . . . . . . . 55 b) Au Gres Series . . . . . . . . . . . . . . 58 c) Newton Series. . . . . . . . . . . . . . . 61 d) Soil analysis carried out by Michigan State University Soil Testing Laboratory . 63 e) Table IA - Summary comparison of guide lines established for each site and soil test results . . . . . . . . . . . . . . . 6h f) Table l5 - Deviations from established guide line for Site B through E. . . . . . 65 9) Soil description, age, and fertilizer program on several blueberry plantations . 66 Site A . . . . . . . . . . . . . . . . 66 Site B . . . . . . . . . . . . . . . . 66 Site C . 67 Site D . 67 Site E . . 68 Site F . 69 Site G . . 69 Site H . 69 LIST OF TABLES Table Page I Soil test results from a l.5 acre area of Au Gres soil. Site A . . . . . . . . . . . . . l7 2 Range in soil results between duplicate 'samples of each composite sample taken from a 1.5 acre area of Au Gres soil. Site A. . . . l9 3 Soil test results from composite samples taken at random and to a depth of eight inches in three small plots, each containing 9 plants growing on an Au Gres soil Site A. . . . . . . 2] A Soil test results from composite samples taken at random and at a depth of l2 to 20 inches in three small plots, each containing 9 plants growing on an Au Gres soil. Site A . . 23 5 Soil test results from composite samples of l2 soil probes each taken in a band at different intervals from the base of one bush in each of 3 plots taken to a depth of 8 inches perpendicular to the row. Site A . . . 25 6 Soil test results from composite samples taken within or near the fertilizer band at a depth of 8 inches in three small plots, each containing 9 plants growing in an Au Gres soil. Site A . . . . . . . . . . . . . . 28 7 Soil test results from four composite samples taken in a four year old blueberry plantation growing on an Au Gres sand. Site B. . . . . . . 3l 8 Soil test results from four composite samples taken in a 25 year old blueberry plantation on a Newton sand. Site C . . . . . . . . . . . 3l 9 Soil test results from four composite samples taken from a three year old blueberry plantation growing on Saugatuck sand. Site D... . . . . . . . . . . . . . . . . . . . 36 IO Soil test results from three composite 'samples taken from a fifteen year old blue- ‘berry plantation growing on Newton sand. Site E. ... . . . . . . . . . . . . . . . . . . 36 List of Tables, cont. ll l2 l3 l4 l5 Soil test results from four composite samples taken from a two year old blue- 'berry plantation growing on Au Gres soil. Site F Soil test results from four composite samples taken from a twelve year old blue- berry plantation growing on Au Gres soil. Site G . . . . . . . . . . . . Soil test results from four composite samples taken from a three year old blue- berry plantation growing on Saugatuck sand. Site H . . . . . . . . . . Summary comparison of guide lines established for each site and soil test results . . Deviations from established guide line for Site B through E. . . . . . . . . . . . . . . Page Al Al #2 64 65 Plate Plate Plate Plate Plate Plate Chm-PUJN -View View View View View Area of of of of of of Site Site Site Site Site FOOt LIST OF PLATES m U 0 CD > O 0 growth of a blueberry bush. Note the high percentage of roots in the first seven inches Page IS 32 33 34 37 39 INTRODUCTION With more than 6,000 acres:of blueberries (Vaccinium corybosum L), having a value in excess.of 4 million dollars annually, Michigan ranks second in production in the United States- Production at the present time is limited to those soils that are not well suited to other field and vegetable crops. The Au Gres, Saugatuck, and Newton 'soil series are representative of those acid soils now used in Michigan for commercial blueberry production. Blueberry soils are generally low in natural fertility. Because of this, the plants reSpond greatly to the use of commercial fertilizer. Until recently a l:l:l ratio fertilizer was conventionally used in Michigan for blueberry production. Recently, growers with mineral soils changed to a 2:l:l fertilizer ratio containing magnesium oxide. 0n organic soils, prOportionally less nitrogen is used. Methods of predicting the fertilizer needs for blueberries have been based on the actual or visual response to fertilizer treatments or upon a chemical analysis of the blueberry leaves. The use of soil tests has been generally restricted to pH determinations. Very little information is available on soil variability and methods of obtaining representative soil samples. Most growers assume that the same methods that are recommended for field crOps are valid for blueberry plantations“ Thismay not be the case because blueberry plants are spaced-at a greater distance than field crops. In addition, blueberries are perennials. Furthermore, fertilizer is not generally applied uniformly in a plantation to the entire soil surface. Another difference is that blueberry roots have a different distribution pattern than do field crops. These four factors perhaps explain why so little success has been obtained when researchers attempted to correlate soil test results with growthresponse and plant tissue‘analysis. The purpose of this study was to attempt to determine a suitable procedure for taking soil samples to be used for soil fertility evaluation in blueberry plantations. REVIEW OF LITERATURE This literature review briefly outlines the general soil fertility diagnosis problems that developed in Michigan with the growth of the blueberry industry. Because it is difficult, if not impossible, to separate the nutrient requirement of this crop from methods used to evaluate nutrient requirements, little effort was made to attempt this- Therefore, the review of literature, in reality, is a statement and explanation of the problems of taking representative soil samples from blueberry plantations. A. Origin of cultivated blueberries Blueberries are becoming an increasingly important cultivated crap in Michigan. Prior to l9l0 there were at least two cultivated plantings of high-bush blueberries] The plantations were composed of high yielding plants which were selected from nearby swamps. Subsequently, Coville selected (27) and bred the wild plants. This work laid the foundation for the new blueberry industry. B. Soils used for blueberry culture The ideal blueberry soil is.a mixture of peatand coarse sand underlaid by a hardpan at the depth of three to four feet (3, ll, 19, 33, 37). Johnston (38) contended that the degree of acidity is more important in blueberry production than is the clay content of the soil. The blueberry plant has no root hairs. The entire root system is very fine and fibrous. It forms a dense mat several inches thick at or near the surface of the soil. The ideal soil for adequate root penetration is Open and porous in structure (l9). C. Soil pH requirements for blueberries The ideal pH level for blueberries is considered to be between 4.0 and 5.2 with the Optimum range being between 4.5 and 4.8 (l8, 33, 34, 39). Blueberries can be produced at higher pH levels if necessary nutrients are maintained in available form. Hill (34) corrected the chlorsis of blueberry plants on-a high pH soil with l00 grams per plant of chelated iron. 0. .Soil fertility and balance Fertilizer recommendations today, as in the past, vary and are often conflicting. Lack of knowledge concerning both soils and the nutrient requirements of blueberry plants undoubtedly account for this unfortunate situation. Kramer and Schrader (42) suggested that the blueberry bush has a low cation requirement and a high anion requirement. Ballinger (5) reported that poor growth results where percent saturation with calcium exceeds l0 percent. Cain (l5) indicated that ammonium nitrogen is superior to nitrate nitrogen when the pH of the soil is near 5.0 or above. E. Fertilizer recommendations It is thought that the soils used for blueberry production do not supply adequate quantities of nitrogen for optimum quality and production. At times, potassium, phosphorus, cal- cium, and magnesium may be limiting plant growth (I3). Because of this situation, the following general fertilizer recommenda- tion is frequently made: I'Avoid nitrates and chlorides, l6-8-8-4* for mineral soils; 8-l6-l6-4 for organic soils. 0n 6 year old and older plants, about 400 pounds per acre (rates depend on age of plants).“ Johnston (37) reported an increase in the yield of blue- berries from the use of high rates of superphosphate. He gave no recorded evidence of the nutrient level and balance in the soil. He also observed that a magnesium deficiency could be induced with the use of high rates of commercial fertilizer. F. Soil testing Considering such circumstances, if possible, it would be desirable to be able to sample-blueberry soils for chemical analysis. With sufficient background, it should be possible with the use of commercial fertilizer to create an Optimum fertility level and balance. The first problem that muSt obviously be faced then pertains to the reproducibility of soil test results. In other words, the sample to be tested must *Percent Magnesium in the oxide form represent a given area of soil. Also, the sample quality and soil test results must be reproducible. G. Soil sampling The emphasis of past work has been on methods used in the chemical laboratory and not on methods of taking a represen- tative soil sample (22, 35, 58). Factors affecting quality of soil samples are: -natural soil heterogeneity, number of subsamples per composite, and methods of handling the sampleaafter it is collected and before it is received by the testing laboratory (22, 35, 45, 52). Variability due to depth of sampling has also been established (8, 55). Welch et al (55) found that samples with similar characteristics can be obtained with a tube, Spade, or trowel. Most of the research on soil sampling has been done on soils used for field cr0p production. Most investigators agree that soil samples should be randomized within the area to be sampled. In areas used for field crops (35, 45, SI, 52) at least 20 soil probes or subsamples per composite sample from 10 acres has been determined to be sufficient for chemical determinations. .Some workers are~reluctant to make such recommendations (44). With fruit cr0ps, it cannot be assumed that soil sampling procedures should be similar to those used for field crops. A procedure frequently followed is to sample under the Spread of the tree or bush limbs (59). Kenworthy (4l) working on fruit trees took (I) samples of the surface soil below the tree limbs; (2) surface soil between trees; and (3) subsoil samples to a depth of three feet. Wilcox (59) tentatively ad0pted a method that involved sampling soils so that there was a 2:l:l ratio between samples from the following locations: (I) under the limbs; (2) midway between two trees in the rOW; (3) in the center of the tree square“ Larson (44) in a study on grapes used samples taken one foot away from the base of the vine and to a depth of six to eight inches. Some workers failed to mention the location of the soil samples taken and the number of cores that were included in the composite sample. Bear (8) stated that one is often led to question the conclusion drawn by investigators from their analytical results when the method of choosing the samples was not indicated or when given, showed the lack of appreciation of the necessity of accuracy in their selection. When working with chemical soil tests as related to blue- berry production Cain (l7) Bally (3), Beckwith (ID, Johnston (37), and others all failed to mention method or methods used in selecting soil samples- Ballinger (5), in his thesis, stated that soil samples were taken to the side of the plants- As stated by Bear, ”one is left in complete amazement when incomplete data are recorded.” PROCEDURE A. Consideration in soil sampling in blueberry plantations Sites for soil samplestudies were selected on the basis of types of soil, methods of fertilizer application,.and age of plants. In this study, the three most productive soil series for blueberry culture in Ottawa County were used: the AuGres, the Newton, and the Saugatuck. Four methods of using fertilizer were considered: (I) band; (2) broadcast in blueberry rows; (3) broadcast between blueberry rows; (4) broadcast over entire area. The age of the plants ranged from 6 to 24 years. B. .Methods of sampling soils Several methods of selecting composite soil samples were investigated. The number of subsamples per composite ranged between I and 40. The samples were taken to a depth of 8 inches with a conventional sampling tube measuring one inch in diameter and IB inches long. At one location, samples were also taken at a depth of l2 to 20 inches. Replications of soil sample treatments ranged from 2 to 4. Subsequent to sampling the soils material was air dried and then well mixed by hand. IO C- Chemical tests on soil samples The following chemical tests were made by Michigan State University Soil Testing Laboratory. Available phosphorus (P), and exchangeable potassium (K), calcium (Ca), and magnesium (Mg). The tests were made by standard procedures. (See Appendix) D. Estimations of soil variability A relatively uniform area of Au Gres sand (Site A), l.5 acres in size, was used for estimating the variability of the soil test results- Samples were taken at random within the area disregarding proximity to blueberry bushes and previous method of fertilizer application. Duplicate composite samples composed of l, 5, IO, 20, and 40 subsamples were collected to.a depth of 8 inches and treated as previously described. Because the ranges in soil test results were greater than desired, the area was resampled on the basis of small plots in an attempt to measure the kind of variation that might occur in a plantation. Three plots in the same area were established each consisting of 9 bushes (II x 54 feet). The same sampling and testing procedures previously described were used on each of the three plots, except that only IO, 20, and 40 soil probes per composite soil samples were taken at two depths, 0 to 8 inches and I2 to 20 inches. II E. Estimation of effect of fertilizer on soil test results Soil test results on the small plots were still variable and apparently reflected the use of commercial fertilizer. Therefore, in an effort to locate the area where the fertilizer had been applied, samples were taken only of the surface soil. One bush was selected from each plot to represent the area. The soil samples, composed of l2 subsamples and taken to a depth of 8 inches, were taken in a line perpendicularto the row at distances of 36, 30, 24, l8, l2, 9, 6, and 3 inches from the base of the plant. The samples were handled as previously described. F. Devel0pment of acceptable soil sampling procedures With the location of the fertilized area known, as reflected by soil test results, the plots were resampled in the fertilized area to determine if the sampling-and soil test results could be duplicated. Composite soil samples were taken to a depth of 8 inches with l, 5, IO, 20, and 40 subsamples per sample and treated as previously described. This sampling procedure was tested the following year on the previously established plots. Plots were divided into subplots of 3 plants each (1+ x l8inches). Composite soil samples were taken 3 weeks after fertilizer was applied. -The sampling and testing procedures previously described were used for each of the 9 subplots. l2 From these data, a proposed method for sampling soil in a blueberry plantation was developed. The method was tested on four sites. The soil samples were taken at random at each site within the fertilized area. A total of 20 subsamples per composite were taken to a depth of 8 inches. Each site was sampled four times. The samples were prepared by conventional methods and tested in the State Laboratory. In order to test the validity of the pr0posed methods which were deveIOped for sampling soils in a blueberry plantation, three other locations were sampled by another person. These soil samples were prepared and tested as has been described. RESULTS AND DISCUSSION This study was undertaken to develop a procedure for obtaining good, representative soil samples from blueberry plantations for soil testing purposes. Preliminary studies indicated that soil test results from a given soil sample could easily be duplicated in the laboratory. Therefore, any great difference in soil test results from replicated samples reflects upon differences in soil samples and not upon the soil test procedure. A. Acceptable ranges for results of repeat soil tests Suspecting that great differences in soil test results from soil samples collected within one area of soil might occur, limits of acceptability were arbitrarily established. If soil tests fell within the limits of acceptability, it would be assumed that the method of sampling was acceptable for further use in soil testing and in making fertilizer recommendations. However, if the soil test results between replications were greater than the specified standards, the sampling methods would be classified as unsatisfactory. The limits of-acceptability that were considered acceptable are as follows: l3 I4 ‘0 I IN- 0.2 of a unit _'0 I+ 7.0 pounds per acre 7C l+ l0.0 pounds per acre 0 m |+ 25.0 pounds per acre Mg t 30.0 pounds per acre 8. Soil fertilitypvariation in a blueberry plantation In order to determine the range in soil test results that might normally be expected in samples taken from a young blueberry plantation, a relatively small area within a large plantation was selected. This area is referred to 'as Site A. Plate I shows this site. The soil within this area was classified by Dr. E. P. Whiteside of the Soil Science Department of Michigan State University as an Au Gres sand which is one of the typical soils used extensively for blueberry production. This soil is acid in nature, imperfectly drained, and sandy. The surface soil is dark gray to pinkish gray underlaid with a dark reddish brown to dark brown sand, containing some iron concretions- A detailed soil description can be found in the Appendix. The blueberry plantation was established in I958 with three year old plants. In I959 the plants were fertilized l5 Plate I View of Site A A seven year old plantation in Au Gres Soil l6 with l2-l2-l2 at the rate of 3 ounches per plant. The fertilizer was placed in a l0 inch ring around each plant. In I960 the same procedure was followed only the rate was increased to 4 ounces. In I961, I962, and I963, ammonium sulfate was applied at the rate of 5 ounces .per bush in a band 24 inches long and 2 inches wide approximately 18 inches from the plant. Only 1 ounce was used in I964. Samples of surface soil were taken within the l.5 acre area of Au Gres soil. They were taken at random without regard to bush location or the use of fertilizer. The soil test results are shown on Table l. The range in soil test results for pH, K, and' Cawere greater than desirable and those described by the ”limits of acceptability." There seems to be‘a close relationship between soil test variability and the number of subsamples in the composite sample that was tested. If it can be assumed that the sample which contained the 40 subsamples is the most representative of the entire area, the need for using a composite soil sample is illustrated by the data in Table I. .There was only a slight difference in soil test results from those samples containing 20 subsamples- l7 Table l. Soil test results from a l.5 acre area of Au Gres soil. Site A. Number of sUESampTes poundspper acre per composite in duplicate pH P K Ca Mg I 5.5 32 I44 296 l20 5.2 32 32 l53 32 5 5.7 30 35 l84 99 5.3 32 32 l28 80 IO 5.6 32 35 l36 80 5.6 32 40 200 80 20 5.l 36 35 I60 64 5.5 34 35 l53 64 40 5.l 40 35 l53 80 5.0 35 35 l84 80 l8 Within an area larger than l.5 acres, it seems logical to assume that natural soil variations would be greater than those within the l.5 acre area. Therefore, within a larger area, soil test variation may be greater than those shown by these data. C. Determining the best number of subsamples per composite The soil at Site A was sampled twice in an effort to attempt to duplicate the soil test results reported in Table I. The same sample procedures were followed. The data in Table 2 show the average of the soil test results from the two samplings as well as the range in soil test results- The average soil test levels tend to be slightly lower than those results reported in Table l. The rangebetween test values where the sample contained only one probeof soil was greater than the limits of acceptability for the tests for K, Ca, and Mg. Where five subsamples were included only the test for Ca exceeded the limits of acceptability. This was also the situation for the samples that contained l0 subsamples- The ranges in tests were all within the limits of acceptability where the composite samples contained either 20 or 40 subsamples. Therefore, it seems that disregarding previous management and fertilizer practices within the l.5 acre area a composite sample should be composed of a minimum 19 Table 2. Range in soil test results between duplicate samples of each composite sample taken from a l.5 acre area of Au Gres soil. Site A. pounds per acre Number of subsamples pH p K Ca . _Mg per composute l 0.3 O ll2 I43 88 5 0.4 2 3 56 l8 l0 0.0 O 5 64 0 20 0.4 2 O 7 0 40 O.l 5 0 3l 0 20 of 20 subsamples- The implications for what might be needed from a ID or 20 acre plantation are great and perhaps beyond the realm of practicability. To further test this method of soil sampling which disregards fertilizer placement, three small plots, each containing 9plants (ID x 54 feet) were selected within the 1.5 acre area. (Site A). Composite samples were taken at random throughout the plot area at two depths; 0-8 inches and I2-20 inches. Ten, twenty, and forty subsamples were composited and tested.3 The results of the chemical tests are recorded in Table 3. The soil test results at the 0-8 inch depth are considerably different than those reported in Table I. This again illustrates the need for the use of a composite soil sample. The variation in soil test results was greater between plots than within plots; however, the variation was reduced when 40 subsamples were taken to make a composite sample(Table'l). Disregarding plots, the pH ranged between 3.7 and 4.5. The test for available phosphorus varied between 27 to 50 pounds per acre. Similarly the values for potassium were l6 to 32; for calcium, Il2 to l28; and for magnesium 32 to 64. 2l Table 3. Soil test results from composite samples taken at random and to-a depth of eight inches in three small plots, each containing 9 plants growing on an Au Gres soil. Site A Soil Test Results pounds per acre Soil probes sgggle pH P K Ca Mg Plot I "id" 4.0 44 24 112 64 20 4.3 50 24 Il2 64 40 4.l 40 24 I20 5l Plot 2 l0 3.9 29 24 ll2 40 20 3.7 29 I6 Il2 4O 40 3.9 40 24 . I20 32 Plot 3 l0 3.9 45 32 ll2 6l 20 4.5 27 24 I20 SI 40 4.0 32 24 I28 6l 22 Such wide differences reflect soil variations caused by the use of commercial fertilizer and by various tillage. The variations in the test results are probably related to the number of subsamples that were taken from the areas to which fertilizer had been added within the plots. The soil test results taken at l2 - 20 inches showed the same trend as 0 - 8 inch depth with a wider variation between plots than within plots (Table 4). In taking these samples, it was noted that the soil contained very few roots. Many probes of soil contained no roots. If they were present they were restricted to the surface few inches of soil. This situation leads one to believe that on the average, soil test results from samples have little practical value. 0. The effect of fertilize:_placement on soil test results To further investigate the wide variation in soil test results, it was decided what effect the method of fertilization had on soil test results. Because band placement of fertilizer had been used on these plots, soil samples were taken near 3 bushes, one from each plot. The samples consisted of l2 soil probes per composite sample which were taken perpendicular to the row to a depth 23 Table 4. Soil test results from composite samples taken at random and at a depth of l2 to 20 inches in three small plots, each containing 9 plants growing on an Au Gres soil. Site A. Soil Test Results pounds per acre Soil probes sgfiple pH P K *Ca Mg Plot l l0 4.3 l3 I6 80 27 20 4.3 24 I6 96 40 40 4.4 I4 I6 88 5I Plot 2 l0 4.4 27 I6 ll2 40 20 4.0 30 24 128 no 40 4.4 32 24 96 40 Plot 3 l0 4.6 23 24 I76 46 20 4.4 27 24 l20 27 40 4.6 34 I6 l04 40 24 of 8 inches and at intervals of 36, 30, 24, IB, 12, 9, 6, and 3 inches from the base of the plant. Twelve probes repre- sented the maximum number of subsamples that could logically be obtained within limits described in this phase of research. The soil test results are recorded in Table 5. Results of the soil test show a decrease in pH between the plant rows at about l8 inches from the plant on plot I and between 9 and l2 inches on plots 2 and 3. This suggests the acidifying effect from the fertilizer band and partially explains some of the variation in test results. (Tables I, 2, 3, and 4) The tests for phosphorus varied greatly, but generally were highest near the base of the plant at the 3-inch distance.' This could be due to the accumulation of grasses about the base of the plant. Plot 2 generally tested higher in phosphorus than Plot l and 3. This may be considered to be due to natural soil variation since the bushes had received no fertilizer containing phOSphorus since l96l. The tests for phosphorus, on an average,.were higher within the l2 inch area. This is considered to be the effect of the phosphorus which was used prior to l96l. Table 5. 25 Soil test results from composite samples of l2 soil probes each taken in a banlat different intervals from the base of one bush in each of 3 plots taken to a depth of 8 inches perpendicular to the row. Site A. giggggggyigggh 36" 30" 24" 18" 12" 9" s" 3" Soil test pfl Plot No. I 5.2 5.3 5.I 4.7 4.9 5.0 5.0 5.I Plot No. 2 4.7 4.8 4.8 4.6 4.4 4.4 4.5 4.0 Plot No. 3 5.0 5.9 5.7 4.7 4.4 4.4 4.8 5.0 Soil test - Pounds per acre of P Plot No. l 24 22 35 35 51 28 36 59 Plot No. 2 36 39 47 39 68 59 50 85 Plot No. 3 27 40 32 30 45 43 39 42 Soil test --Poundspper acre of K Plot No. I 32 40 40 32 32 40 48 40 Plot No. 2 24 24 32 24 24 24 32 24 Plot No. 3 32 48 35 32 24 32 40 32 Soil test - Pounds_per acre of Ca Plot No. l l20 I20 l20 l04 88 88 88 96 Plot No. 2 l20 I04 I04_ 88 Il2 l20 I20 96 Plot No. 3 l84 l84 l28 l04 ll2 l53 l53 I36 Soil test - Pounds per acre of Mg Plot No. I 53 45 80 45 64 72 64 80 Plot No- 2 45 32 53 64 64 64 45 32 Plot No. 3 80 l36 53) 53 ‘32~ 64 99 80 ....... 26 The tests for potassium showed between plot variation as well as within plot variation. The use of fertilizer containing potassium prior to l96l was not reflected in soil test results. The tests for potassium tended to be lower in the areas of maximum acidity. This-is logical in that the hydrogen ions from ammonium sulfate fertilizers probably exchanged with the potassium ions thus decreasing the test values for potassium. The tests for calcium and magnesium varied as much as l00 per cent. Such variation is not easily explained. After collecting so many soil samples and analyzing the soil test results, it became evident from the variability of the test results that in order to obtain a representative sample, several factors would have to be considered. While soils that are used for blueberry production are naturally acid and test low in phOSphorus,.potassium, calcium, and magnesium,.there apparently is considerable natural soil variation. The variation in soil test results appears to increase with the use of commercial fertilizer, especially when it is banded. The location of the blueberry roots undoubtedly has a profound effect upon soil test levels. 27 In young plantations it was observed less than a third of the surface soil contain roots. This undoubtedly affects soil fertility levels and soil test results. Vegetation between plants, especially down the row varies greatly as to number and species. This also influences soil test results -- at least from a theoretical point of view. The last consideration is the number of subsamples that should be composited and tested to represent the average condition within a given area -- the area occupied by the roots of the plants. In order to measure averagefertility conditions by the use of soil tests, it would seem that soil samples should be collected near the plant where the roots are actively growing and in the area where fertilizer had been used. Because it is not possible, in most instances, to see fertilizer particles it therefore becomes necessary to take several subsamples and composite them. With this in mind three small plots each containing 9 plants were selected on Site A on the Au Gres soil. .Samples composed of varying number of subsamples were collected within or near the location of the fertilizer band as shown in Table 6. In interpreting the data in Table 6,consider the test results from the composite sample which contained 40 subsamples as the standard. Deviation from these values should fall within 28 Table 6. Soil test results from composite samples taken within or near the fertilizer band at a depth of 8 inches in three small plots, each containing 9 plants growing in an Au Gres Soil. Site A. SoiTprobes pounds per acre gaggle pH P K Ca Mg PIOt 1° I 4.8 61 37 128 I60 5 5.0 56 37 Il2 I60 l0 5.I 63 43 ll2 I60 20 5.0 53 27 ll2 I60 40 4.9 SI 27 ll2 I36 PIOt 2' l 4.7 56 37 120 128 5 4.9 46 37 I36 l28 l0 4.8 so 37 I28 128 20 4.9 42 37 l20 l28 40 4.9 SI 27 ll2 l28 Plot 3. I 5.0 53 37 I76 I73 5 4.8 39 37 I36 I60 I0 5.I 53 43 I60 l36 20 5.3 48 43 I53 l8l 40 5.0 45 43 l53 ‘2lO 29 the limh5.of acceptability if they are to be considered useable for evaluating soil fertility levels and balance. Since the pH values did not deviate more than those established as the standard, all of the pH values reported in this table are considered to be acceptable. The phosphorus, potassium, calcium, and magnesium varied more than the pH, however, the variation was less than that in the previous sampling studies (Table I, 2, 3, 4). Under the condition that existed, more than l0 subsamples per plot were required to satisfy the standards that were established. E. Reproducibility of soil test resplts from samples taken in blueberry plantation Considering the soil test results that were obtained near individual plants, and on small plots, it seemed logical to evaluate the heterogeneity of soil tests obtained from samples taken from commercial blueberry plantations. The Specifications for the sampling methods employed were as follows: (I) the soil should be taken from the fertilizer zone; (2) the soil should be representative of one soil series; (3) the soil should consist of 20 subsamples; (4) the samples shOuld be taken to-a depth of 8 inches. Four composite soil samples from each site were collected taking these factors into consideration. Samples were taken from 30 four fields labeled as Sites B, C, D, and E. The soil test results were averaged to obtain an estimate of the fertility levels within any one plantation. Deviations from the mean were evaluated on the basis of the previously described limits of acceptability. The soil test results from Site B, are shown in Table 7. This site is on Au Gres soil and the plantation was four years old (Plate 2). The tests for pH were within acceptable limits, as were the individual tests for phosphorus, calcium, and magnesium. Two of the tests for potassium were outside of the acceptable range by approximately l5 per cent. The soil test results from Site C are shown in Table 8. This site is characterized by a 24 yearold plantationonta Newton sand (Plate 3). The tests for pH and magnesium were all within the limits of acceptability. This is especially important because these two are more likely to be limiting factors than are phOSphorus, potassium, and magnesium. Two of the tests for phosphorus and potassium and one of the tests of calcium were just barely outside of the range of acceptability. Soil test results for Site D,.are shown in Table 9. This site is characterized by a threesyear-old plantation growing on a Saugatuck sand (Plate 4). 3l Table 7. Soil test results from four composite samples taken in a four year old blueberry plantation growing on an Au Gres sand. .Site B. _. pounds per acre a P” P K Ca Mg Sample I 4.3 69 lO4 ‘ 208 50 Sample 2 4.5 73 I36* 224 6I Sample 3 4.5 66 83% 248 78 Sample 4 4.4 75 112' 224 50 Mean 4.4 7I l09 ....226.., 57 Table 8. Soil test results from four composite soil samples .taken in a 25 year old blueberry plantation on a Newton sand. Site C. pounds per acre pH i ‘P K .Ca. Mg Sample I 5.I I62* I66 409 50 Sample 2 5.2 I74 _ l52 488 78 Sample 3 5.I I68 I80? 5l2* 67 Sample 4 5.2 192* 144% 480. 19 Mean 5.2 I74 I6] 472 54 *Outside the limits of acceptability 32 PLATE 2 View of Site B A four year old plantation in Au Gres Soil 33 PLATE 3 View of Site c A twenty-five year old plantation on Newton soil 34 PLATE 4 View of Site 0 A three year old plantation in Saugatuck soil 35 When the soil tests were compared with the limits of acceptability, only the potassium and calcium tests exceeded the standards. The potassium test exceeded the limits by only 2 and 9 pounds per acre and the calcium by 7 pounds. These are considered to be not greatly outside the limits. For all practical purposes in making fertilizer recommendations, they are satisfactory. The soil test results for Site E are shown in Table I0. This site is characterized by'a l5 year-old plantation growing on a Newton sand (Plate 5). The test results from the three soil samples taken from this field were within the limits of acceptability with one exception. The test for potassium exceeded the limit by only 5 pounds in one instance. This is not considered to be greatly significant from the standpoint of reproducibility of soil test results or in the area of making fertilizer recommendations. When comparing the data obtained from these four sites with the range established for this study, the results showed that all l5 soil tests were within the guide lines for pH and magnesium. Thirteen of the phosphorus, I2.of the calcium, and 9 of the potassium soil tests also fell within the guide 36 Table 9. Soil test results from four composite samples taken from a three year old blueberry plantation growing on Saugatuck sand. Site D. pounds per acre pH P K Ca Mg Sample I 4.4 82 69* I44 I6 Sample 2 4.6 82 92 200* I9 Sample 3 4.5 82 84 I44 l6 Sample 4 4.6 77 98* I84 35 Mean u.s 81 86 A 168 22 Table I0. Soil test results from three composite samples taken from a fifteen year old blueberry plantation growing on Newton sand. Site E. pounds per acre pH P K Ca Mg Sample I 4.8 I74 I66* 200 3l Sample 2 4.8 I68 I44 I68 I9 Sample 3 4.9 I74 I44 l84 I9 Mean 4.8 I72 l5l l84 23 *Outside the limits of acceptability '37 PLATE 5 View of Site E A fifteen year old plantation in Newton soil 38 lines. 0f the 75 separate test results, only II fell outside of the range established. However, five of these II were only 2 to 9 pounds per acre outside of the established ranges- Looking backward, all conceivably could have been within the limits of acceptability if the limits had not been so narrowly defined. A summary of deviation from the established guide lines and a summary of a comparison of the actual soil tests with the satisfactory limits for each of these sites is found in the Appendix (Tables I4 8 I5). Also a brief description of each soil type and the soil management treatments are summarized. F. Final testing_of the-proposed sampling method Because the soil test results fell within or very close to theproposed limits of acceptability, the soil sampling procedure was evaluated by outlining the sample methods to a fellow worker and then having him take samples by this method from three different blueberry plantations. Four separate composite soil samples were taken at random from each site. The first plantation was labeled Site F and the soil was an Au Gres sand. The soil test results from this l0 year old plantation are shown in Table II. All of the soil test values fell within the limits of acceptability. 39 PLATE 6 Area of root growth of a blueberry bush. Note the high percentage of roots in the first seven inches. £10 The second plantation was labeled Site G. The soil at this site was also an Au Gres sand. The soil test results from this I2 year old plantation are shown in Table I2. 0f the 20 soil test results for this site, I8 fell within the guide line range. Of the two values outside the range, one phosphorus test fell outside by 7 pounds per acre and one calcium test by 5 pounds per acre. A third plantation was labeled Site H. The soil at this site was mapped as Saugatuck sand. The soil test results from this 3 year old plantation are shown in Table I3. 0f the 20 soil test results on this site, l9 fell within the required range. One test for potassium fell outside the accepted range by two pounds per acre. A summary of the characteristics of each soil type and the important management practices at each site are shown in the Appendix. The experimental results obtained at Sites F, G,.and H, on which separate test results were made, show that 57 of these tests fell within the established range. The three values falling outside the accepted range occurred at Sites H and G where 2 pounds per acre of potassium and 5 and 7 pounds per acre of calcium and phosphorus occurred respectively. 4I Table II. Soil test results from four composite samples taken from a two year old blueberry plantation growing on Au Gres soi . Site F. pounds_per acre pH P K Ca Mg Sample I 4.3 l50 l04 280 I6 Sample 2 4.I I50 l04 288 I9 Sample 3 4.0 I62 118 280 19 Sample 4 4.0 I60 l04 272 3] Mean 4.I l55 I08 280 2I Table I2. Soil test results from four composite samples taken from a twelve year old blueberry plantation growing on Au Gres soi Site G. ppunds per acre pH P K Ca Mg Sample I 4.0 246 98 266* 3I Sample 2 4.I 246 I04 232 35 Sample 3 4.I 264* 98 224 35 Sample 4 4.0 244‘ 92 224 31 Mean 4.I 247 98 236 33 *Outside the limits of acceptability 42 Table I3. Soil test results from four composite samples taken from a three year old blueberry plantation growing on Saugatuck sand. Site H. pounds per acre pH .P K Ca Mg Sample I 3.6 l20 98* 208 3I Sample 2 3.5 116 112 224 35 Sample 3 3.6 l20 ll2 208 35 Sample 4 3.6 112 118 224 35 Mean 3.6 ll6 ll0 2l6 34 *Outside the limits of acceptability 43 Only fourteen from a total of I35 chemical tests carried out on these seven plantations (B, C, D, E, F, G, and H) were outside of the established range set up for this study. Of these, 9 were only 2 to ID pounds outside of the established ranges. Considering the results obtained on the soils at these seven sites it was concluded that this procedure of taking soil samples can confidently be used to obtain a soil sample that will effectively represent the fertility level of the area sampled. SUMMARY The purpose of this study was to attempt to deveIOp a suitable procedure for taking soil samples to be used for soil testing purposes from blueberry plantations. Preliminary studies indicated that the State Soil Testing Laboratory could do a satisfactory job of testing soils and that the reproducibility of the test results from a given sample of soil was of a high order. Soil tests from samples taken at random in a blueberry plantation without regard to location of bushes or previously applied fertilizer, or natural soil variation showed a high magnitude of variation. The variation was large enough that the test results could not be satisfactorily used for evaluating the fertility level or balance in the soil. When the soil samples were taken at random within the plantation but within the fertilizer zone, it was found that with the use of 20 soil probes per composite, the soil test results were within or very close to the limits of acceptability established in this study. This situation was obtained by taking soil samples to a depth of 8 inches. The method was used on four selected sites. Tests for pH and available ph05phorus, potassium, calcium, and magnesium were made on replicated samples for each site. 0f the 75 44 45 separate tests made, only ll fell outside of the-range considered to be acceptable. Five of these were just slightly outside of the acceptable range. To further test this method,.a summer worker who had not taken soil samples previously was given directions on this method of sampling soil. He took replicated soil samples from three plantations. The soil test results-showed that the proposed method of taking soil samples from a blueberry plantation was satisfactory. It is hOped that this study has laid the foundation for attempting to correlate the growth of blueberries, and the reSponse from fertilizer to soil test results. GENERAL DISCUSSION The following discussion is an effort to outline a suitable method for taking soil samples from blueberry plan- tations. The thoughts expressed in this section are based upon the research reported in this thesis as well as upon the research and observation of others. The outlines takes hto consideration the requirements of the State Soil Testing Laboratory at the time this is written. I. Equipment .1, 5. Clean pail - ID to l2 quart size - to be used for collecting and mixing the soil samples Soil probe --for collecting subsamples for compositing procedure. Soils map of plantation. Notebook for recording the soil sample number as well as the location from which the samples were derived. Soil sample bags or carton. 2. Sampling method I. Inventory the condition in the plantation. Know where unrepresentative areas exist and do not take samples from such areas. Consider information on soils map as well as the characteristics that can be seen. 46 ”47 2. Question the farmer about methods and placement of commercial fertilizer. 3. Select areas of uniform soil to be sampled that are no larger than I0 acres. 4. Take composite soil samples composed of a minimum of 20 subsamples. 5. Take soil samples to a depth of 8 inches. 6. Take soil samples at random within the field but within the areas where fertilizer has previously been applied and from within the area occupied by the roots of the plant. 7. Avoid including areas where brush has been burned, where tile are located, where fertilizer was spilled, .and areas near gravel roads- 3. Soil sample preparation I. .Mix well the 20 subsamples. If the soil is too wet to mix, place in a sheltered location and allow to air dry before mixing. 2. Take a subsample (one pint) of the composite and place in soil sample carton. 3. Label each carton and keep a record in the notebook on each sample. 4. Send soil sample to the State Testing Laboratory. 48 If these procedures are-followed,.reasonably accurate soil samples will be taken. They can with-confidence be submitted to the State Soil Testing Laboratory as represen- tative of the soil in part or in the whole of a blueberry plantation. d 0 U1 LITERATURE CITED Amling, H. J. Influence of nutrient-element supply on leaf composition and growth of highbush blueberry (Vacinium corymbosum L.) with special reference to importance of sampling date on leaf and fruit composition of field grown blueberries. Ph.D. Thesis. Michigan State University, East Lansing, Mich. I957. Bailey, J. S.,.and M. Drake. Correcting magnesium deficiency in cultivated blueberries and its effect on leaf potassium, calcium and nitrogen. Proc. Amer. Soc. Hort. Sci. 63: 95-99, I954. . T. Franklin,.and J. L. Kelly. Blueberry culture in Massachusetts. Mass. Bul. 358: I-20, I939. . .. C. T. Smith,.and R. T. Weatherly. The nutrient status of the cultivated blueberry as . revealed by leaf analysis. Proc. Amer. Soc. Hort. Sci. 54: 205-208,_I949. Ballinger, W. E. Nutritional conditions of Michigan blue- berry' plantations. Ph.D. Thesis, Michigan State University, East Lansing,.Mich., I957. .Tf}, A. L. Kenworthy, H. K. Bell, E. J. Benne, and S. T. Bass. Relationship between nutrient- ‘element content of blueberry foliage and fruit. Micgigan Agr. Expt-.Sta. Quart. Bul. 40: 906‘9ll, 95 . . 1 . Nutritional conditions of Michigan blueberry plantations. Michigan Agr. Expt. Sta. Quart. Bul. 40: 896-9l4, I958. Bear, E. R., and G. M. McClur. Sampling soil plots. Soil Sci. 9: 65-75, I920. 49 l0. ll. l2. l3. I4. l5. l6. l7. I8. 19. 20. 2l. 50 Beckwith, C. S. The effect of fertilizer on blueberry Soil Sci. IO: 309-4l4, I920. Location and preparing fields for cultivated blueberry. N.J. Agr. Expt. Sta. Cir. “'73, I9LI'3. ..S. Coville, and C. A. Doehlert. >Biueberry CUTture. N. J. Agr. Expt. Sta. Cir. 229, I937. Bell, A. P., and S. F. Thorton. The effect of season and fertilizer on results of rapid chemical tests. Soil Sci. Soc- Amer. Proc. 2: l67—l7l, I937. Bell, H. K.,.and S. Johnston. Hints on Blueberry Growing. Michigan State University Cooperative Ext. Serv. F-Il9, I962. Boller, C. A. Growing blueberries in Oregon- ,Ore. Agr. .Expt. Sta. Bul. 499, 1951. Cain, John C. A comparison of ammonium and nitrate nitro en for blueberries.lAfiaa.Soc. Hort. Sci. 59: I l-l67, I952. How are your blueberries doing? New York State Agr. Expt. Sta. Farm Research, Jan. I953. Blueberry chlorsis in relation to leaf pH and mineral composition. Proc. Amer. Soc. Hort. SCI. 64: 6I-69, I954. Cultivated blueberries must be cultivated New York State Expt. Sta. Farm Research, Jan. I952. Highbush blueberries a cultivated fruit. ‘NewTYork State Expt. Sta. Farm Research, April I949. and R. W. W. Holley. A comparison of chlorotic and green blueberry leaf tissue with reSpect to free amino acid and basic cation contents. Proc. Amer. Soc. Hort. Sci. 65: 49-53, I955. and G. L. Slate. Blueberries in the home garden. Cornell Ext. Bul. 900: l-22, I953. 22. 23. 24. 25. 26. 27. 28. 29. 30. 3I. 32. 33. 34. 35. 36. SI Cline, Marlin G. Principles of soil sampling. Soil Sci. 58: 275*288, l9 4 Methods of collecting and preparing soil samples. Soil Sci. 59: 3-5, I944. ChristOpher, E. P., and V. G. Shutak. Influence of several soil management practices upon theyield of cultivated blueberries. Proc. Amer. Soc. Hort. Sci. 49: 2ll-2l2, I947. Collison, R. C. Making soils acid for blueberries. New York State Agr. Expt. Sta. Farm Research, I942- Clark, J. H. Blueberries under mulch. N.J. Agr. Bul. I8: l~2, I936. Darrow, G. M., J. B. Demaree, and W. E. Tomlinson, Jr. Blueberry growing. U.S. Dept. Agr. Farmers Bul. I95l. Doehlert,.C. A. and J. W. Shive. Nutrition of blueberry . (Vaccinum corymbosum L.) in-sand culture- Soil Sci. 4l: 34l-350, I936. Dates for applying blueberry fertilizer. Proc. Amer. Soc. Hort. Sci. 38: 4SI-454, l94l. Facts about fertilizing blueberries. ' J.J. Agr. Expt. Sta. Cir..550, 1953. Eaton, E. L. The Blueberry. Dominion of Canada Dept. of Agr. Pub. 754, l-I6, I943. Goheen, A. C. The cultivated highbush blueberry, U. S. Dept. Agr.,-Yearboek1l953:7832789. Harmer, P. M. Soil reaction and growth of blueberry. Soil Sci. 9: I33-I4l, I944. Hill, R. G. The blueberry chlorsis problem. Ohio State Hort. Proc. I08: l64-l76, I954. Jackson, M. L. Soil chemical analysis. Prentice-Hall, Inc., New Jersey, I958. Jacob, W. C. and A. Klute. Sampling soils for physical and chemical prOperties. Soil Sci. Soc. Amer. Proc. 20: l70-l72, I956. 37. 38. 39. 40. 4I. 42. 43. 1111. 45. 46. 47. 48. 52 Johnston, Stanley, Mich. Agr. Expt.Sta. Quar. Bul. 24: 307-3l0, l94l. Mich. Agr. Expt.Sta. Spec. Bul. No. 252, I939. Mich. Agr. Expt.Sta. Cir. Bul. l88, I959. Jones, J. B., H. J. Mederski, D. J. Hoff,.and J. H. Wilson. Effect of drying some Ohio soils upon the-soil test for potassium. Soil Sci. Soc. Am. Proc. 25: l23-l25, l96l. Kenworthy, A. L. Nutritional condition of Michigan orchards: -a survey of soil analyses and leaf composition. Mich. Agr. Expt. Sta. Tech. Bul. 237: I-30, I953. Kramer, A., and A. L. Schrader. Significance of the pH of blueberry leaves. Plant Physiol. 20:-30~36, I945. Larson, R. P., A. L. Kenworthy, H. K. Bell, and-S. J. Gamble. Effects of potassium and magnesium fertilizers and dolomitic lime on nutritional 1:11:2595632'811131‘? i221: firmware132.2573”- Nutritional conditions of concord vineyards TH Michigan. ll. Soil analysis in relation to production. Mich. Agr. Expt. Sta. Quar.‘ Bul. Vol. 39: 78-87, I956. Longnecker, E. D. How to take accurate soil samples. Mich. State Univ. COOperative Ext. Service,.F~278, l96l. Merrill, T. A. Acid tolerance of highbush blueberry. Mich. Agr. Expt.-Sta. Quar. Bul. 22: ll2-ll6, I939. Mikkelson, D. S., and C. A. Doehlert. Magnesium deficiency in blueberries. Proc. Am. Soc. Hort. Sci. 55: 289-292, I950. Mowry, H., and A. F. Camp. Blueberry culture in Florida. Ag. Expt. Sta. Univ. of Fla. Bul. I94:-280-297, I950. 49. 50. SI. 52. 53. 54. 55. 56. 57. 58. 59. 53 Reed, J. F., and J. A. Rigney. Soil sampling from fields of uniform and non-uniform appearance and soil types. Jour. Amer. Soc. Agr. 39: 26-40, I947. Reynolds, E. B. and J. C. Smith. The effect of fertilizer treatments-and rates of sampling on the easily soluble phOSphorus in-soil. ' Soil.Sci. Soc. Amer. Proc. ll: l98-200, I946. Rigney, J. A. and J. F. Reed. Some factors affecting the accuracy of soil sampling. Soil Sci. Soc. Amer. Proc. IO: 257-259, I956. Robertson, L. S. Soil sampling for fertilizer recommen- dations for field and vegetable cr0ps. Mich. State Univ. Publication. Runge, E. C. A. A new method of sampling Illinois soils. Fertilizer Solutions. July I965, pages l0, II, and 35. Savage, E. F., and G. M. Darrow. Growth response of blueberries under clean cultivation and various kinds of mulch material. Proc. Amer. Soc. Hort. Sci. 40: 338-340, I942. Schuartze, C. D. and A. S. Myhre. Growing blueberries in the Puget Sound region of Washington. Wash. State Univ. West Wash. Expt. Sta. Cir. No. 245, I9 5. Tukey, H. B., and M. M. Meyer, Jr. Nutrient applications to dormant plants. American Nurseryman, June I965, pages.5-8. Vetch, J. O. The samplin of soils. Mich. Agr. Expt. Sta. Quart. Bul. 7: 9 ~98. Welch, D. D., and J. W. Fitts. Some factors affecting soil sampling. Soil.Sci. Soc. Amer. Proc. 20: 54-56, I956. Wilcox, J. c. Soil sampling technique in orchards. Sci. Agr. 28: 321-332, 1948. APPENDIX SAUGATUCK SERIES The Saugatuck series are imperfectly to poorly drained ground-water Podzols developed in deep, acid sands. Sauga- tuck soils have a very stnangly cemented (ortstein) in the upper B horizons. Soil Profile: Saugatuck Sand A0 2-0” Organic mat of partially decomposed leaves and twigs, with a mass of fine roots. I to 4 inches thick. AL 0-2” Sand: black (IOYR 2/I - 5 YR 2/I): very weak, fine granular structure; very friable; contains a mass of fine roots; strongly to extremely acid; abrupt smooth to wavy boundary. I to 6 inches thick. A2 2-IO“ Sand: light grayish brown (IOYR 6/2) pinkish gray (7.5YR 7/2) or reddish gray (SYR 5/2) single grain (structureless); loose; very strongly to extremely acid; abrupt wavy to irregular boundary. 2 to l5 inches thick. 55 B2IH 822 B3 l0-l6” ir l6-26” 26-36” 56 Sand: very dusky red (2.5YR 2/2) or dark reddish brown (SYR 2/2 - 3/4); sand strongly cemented; massive (structureless); very strongly to extremely acid; abrupt to clear wavy to irregular boundary. 4 to l2 inches thick. Sand: reddish brown (SYR 4/4) reddish yellow (SYR 5/8-4/8) or dark reddish brown (SYR 3/4); massive to moderate, medium or thick, platy structure; contains a mass of fine roots along horizontal planes; strongly cemented in upper part, with gradual change to weakly cemented in lower part; strongly to extremely acid; gradual irregular boundary. 6 to I8 inches thick- Sand: strong brown (7.5YR 5/6), reddish yellow (7.5YR 7/6), or light yellowish brown (IOYR 6/4) which contains numerous vertical channels or tubes, from less than I mm to about 3 mm in diameter and l/4 to 5 inches long, and blotches of dark reddish brown (5 YR 3/3) and dark brown (7.5YR 4/4); the redder or stronger color is in the center of the channels, 57 with a gradual fading of color outward; single grain.; (structureless); loose; medium to very strongly acid; gradual wavy boundary. 6 to I4 inches thick. C 36”+ Sand: very pale brown (IOYR 7/4), pale brown (IOYR6/3), or light brownish gray (IOYR 6/2) which contains very thin channels or tubes of strong brown (7.5YR 5/6) and dark brown (7.5YR 4/4); channels are common in upper part, and diminish in quantity with depth; single grain (structureless) loose; medium to very stronglyacid. Topography: Nearly level to gently rolling areas in lake and till plains. Drainage and Permeability: Imperfectly to poorly drained. Runoff is slow to medium. Permeability is slow to moderately rapid. AU‘GRES SERIES The Au Gres series includes imperfectly drained Podsols deveIOped in thick sandy glacial drift. Soil Profile: Au Gres~Sand A0 2-0” Organic mat, including leaves and other plant remains in various stages of decomposition. One-half to 3 inches thick. AI O-l” Very dark gray (7.5YR 3/l) or dark brown (7.5YR 3/2) sand; moderately high organic matter content; very weak fine granular structure; very friable; medium acid; abrupt smooth boundary. I to 4 inches thick. A2 l-S” Pinkish gray (7.5YR 7/2) or light gray (SYR 7/I) sand; very weak fine platy structure, to single grain; loose; strongly to medium acid; abrupt irregular boundary. 4 to l2 inches thick. BZIh 5-8“ Dark reddish brown (SYR 3/3) or dark brown (7.5YR 4/4) sand; very weak coarse subangular blocky structure; very friable to nearly loose; contains a few hard iron concretions; strongly to medium acid; gradual irregular boundary. l to 5 inches thick. 58 59 822ir 8-I4" Dark brown (7.5YR 4/4), reddish brown (SYR 4/4), or strong brown (7.5YR 5/6) sand; single grain to very weak coarse~subangular blocky structure; loose to very friable; contains a few hard concretions and chunks; strongly acid; grandual irregular boundary. 4 to I0 inches thick. B3g I4-30'I Reddish yellow (7.5YR 6/6), mottled with strong brown (7.5YR 5/6) and very pale brown (IOYR 7/3) sand; mottles are few to many, medium, and distinct; single grain; loose; strongly to medium acid; gradual irregular boundary. IO to 20 inches thick. Cg 30”+ Pinkish gray (7.5YR 7/2) or light gray (IOYR 7/2), mottled with pale brown (IOYR 6/3) and brownish yellow (IOYR 5/6) sand;:mottles are few to many, medium, and distinct;single grain; loose;medium acid to neutral. Range in Characteristics: The Al is absent in some areas. Where Au Gres soils grade toward the Saugatuck soils the upper B horizon is weakly cemented, and it contains numerous chunks of cemented material. The degree of deveIOpment of the Podzol solum ranges from weak to strong. The thickness of the solum ranges from 25 to about 40 inches. The depth to mottling 69 ranges down to about I8 - 20 inches. Where Au Gres soils grade toward the Croswell soils the depth to mottling approaches the maximum given. The reaction of the solum ranges from strongly to slightly acid. Sand and loamy sand types have been recognized. Colors refer to moist conditions. Topography: Level to gently sloping areas in outwash plains and till plains. Drainage and Permeability: Imperfectly drained. Runoff is slow to very slow. Remarks: AuGres soils were formerly included with the Saugatuck Series. Saugatucksoils have Ortstein B horizons. NEWTON SERIES Newton series comprises Humic-Gley soils devel0ped in strongly to very strongly acid sands. Soil Profile: AP A2 89 0-811 8-I2” l2-30” Newton loamy fine sand. Loamy fine sand: very dark brown (IOYR 2/2) or very dark gray (IOYR 3/I); very weak, medium, granular structure; very friable; medium to very strongly acid; abrupt smooth boundary, 7 to ID inches thick. Loamy fine sand: very dark gray (IOYR 3/I); few, fine distinct mottles of yellowish brown (IOYR 5/6-5/8) in lower part; very weak, coarse, granular structure; very friable; strongly to very strongly acid; clear wavy boundary. 2 toi6 inches thick. Loamy sand to sand: grayish brown (IOYR 5/2) or gray (IOYR S/I) mottled with yellowish-brown (IOYR 5/6-5/8), dark yellowish brown (IOYR 4/4), .and strong brown (7.5YR 5/6), mottles are common, medium, and distinct in the upper part, with gradual change to many, coarse and distinct in lower part; single grain structure; loose; strongly to very strongly acid; diffuse irregular boundary. l4 to 30 inches thick. 6l 62 Cg 30”+- Sand: yellowish brown (IOYR 5/6) or brownish yellow (IOYR 6/6 - 6/8) mottled with gray (IOYR 5/I), dark yellowish brown (IOYR 4/4), and dark brown (7.5YR 4/2 - 4/4); mottles are common, medium, and distinct; single grain structure; loose; strongly to very strongly acid; gradual structure; loose; strongly to very strongly acid; gradual change below 60 inches to medium or slightly acid reaction. TOpography: Nearly level to slightly depressed areas in outwash and lake plains. Drainage and Permeability: Poorly to very poorly drained. Runoff is very slow to ponded. Permeability is very rapid. Native Vegetation: Marsh grasses, reeds, and sedges with some aspen, pin and black oak. Soil Analysis Carried Out by the Michigan State University Soil Testing Laboratory l. pH, determined by Glass Electrode using a Beckman Model H-2 pH meter using a l:l soil to water ratio. 2. Phosphorus, extrated by .025 NHCI + .03 N NHAF (Bray P1). 3. Potassium, calcium, and magnesium were extracted with neutral normal ammonium acetate. .The potassium and calcium were determined quantitatively on the Model 2I Coleman Flame Photometer and the magnesium was determined flame photometrically using a Beckman DU with a flame attachment at a wavelength of 285.2 millimicrons- Potassium, calcium,.magnesium and phosphorus were extracted from the soil employing soil to extract ratios of I:8. 63 Table I4. Summary Comparison of Guide Lines Established for Each Site and Soil Test Results Pounds per acre P K Ca Mg Site B Mean 7l 109 226 57 Guide Line Range 64-- 78 99'- ll9 20l - 25l 27 - 87 Soil Test Range 66 - 75 83 - I36 208 - 248 50 - 78 Site C Mean I74 l6l 472 54 Guide Line Range I67 - I8I l5l - l7l 447 - 497 24 - 84 Soil Test Range I62 - I92 I44 - I80 409 - 5I2 l9 - 78 Site‘D Mean 8l 86 I68 22 Guide Line Range 74 ->88 76 - 96 I43 - I93 0 - 52 Soil Test Range 77 --82 69 - 98 I44 - 200 I6 - 35 Site E Mean I72 ISI I84 23 Guide Line Range I65 - I79 I4l - l6l l59 - 209 0 - 53 Soil Test Range I68 --l74 I44 - I66 I68 - 200 I9 - 3l 64 Table I5. Deviations from Established Guide Line for Site B through E PEUnds per acre Site none none I6 I7 none none Site none 5 - ll 7 9 38 - I5 none Site none none 9 2 0 - 7 none Site none none 0 5 none none 65 Soil Description, Age, and Fertilizer Program on Several Blueberry Plantations Site A This soil is anAu\Gres which is acid in nature, imperfectly drained, and sandy. The surface soil is dark gray to pinkish gray underlaid with a dark reddish brown to dark brown sand, containing some iron concretions. A detailed description of this soil can be found in the Appendix. The blueberry plantation was established in 1958 with three year old plants. In 1959 they were fertilized with a 12:12:12 at the rate of 3 ounces per plant in a IO inch ring around the plants. In I960 the same procedure was followed only the-rate was increased to 4 ounches. In 1961, I962, and 1963 ammonium sulfate was applied at the rate of 5 ounces per bush in