LIBRARY 
 STATE PLANT BOARD 
 
 June 1952 E-839 
 
 United States Department of Agriculture 
 
 Agricultural Research Administration 
 
 Bureau of Entomology and Plant Quarantine 
 
 EFFECT OF DDT AND CHLORDANE APPLIED TO CONTROL 
 
 JAPANESE BEETLE LARVAE ON THE YIELD OF GRASS, 
 
 RYE, SOYBEANS, AND CORN 
 
 By W. E. Fleming and W. W. Mainesl' 
 Division of Fruit Insect Investigations 
 
 DDT at the rate of 25 pounds per acre or chlordane at 10 pounds per 
 acre, mixed intimately with the upper 3 inches of soil, is authorized for 
 the treatment of beds and plots in commercial nurseries that are under 
 quarantine because of the Japanese beetle (Popillia japonica Newm.). 
 These toxicants are recommended also for application to the surface of 
 established turf to protect it from damage by this insect.— 
 
 Large areas of turf are treated with these toxicants, and rye, soy- 
 beans, and corn are used by commercial nurseries in rotations for soil 
 improvement. In 1947 an experiment was undertaken to simulate these 
 applications of chlordane and DDT to large areas, maintaining them 
 according to accepted procedure, to determine the effect of the toxicants 
 on growth of the crops. This experiment was concluded in 1951 after four 
 growing seasons and the results are presented in this report. 
 
 Establishment of Field Plots 
 
 A 3-acre field at Moorestown, N. J., that had not been under cultiva- 
 tion for several years was selected for this experiment. The soil in 
 this field is sassafras sandy loam, which is used in the production of 
 general farm crops and nursery stock in southern New Jersey. A light- 
 brown sandy loam about 6 inches deep, with a scattering of well-rounded 
 quartz gravel throughout, rests on a sandy clay subsoil. Drainage is well 
 established. Analysis^' of this soil showed that the pH was 5.0 and that it 
 was relatively low in organic matter, magnesium, phosphorus, and potassium, 
 
 1/ The writers acknowledge the assistance of L.W. Coles, C. A. 
 Perkins, H.W. Strabel, and A. R. Whitcraft, of the Japanese Beetle 
 Laboratory, Moorestown, N.J., in conducting this investigation. 
 
 2/ Fleming, W. E. 1950. Protection of turf from damage by 
 Japanese beetle grubs. U.S. Dept. Agr. Leaflet 290, 8 pp. 
 
 3/ Made by the Soil Testing Laboratory, New Jersey Agricultural 
 Experiment Station, New Brunswick, N.J. 
 
-2 
 
 During the summer of 1947 an area 330 by 340 feet in this field was 
 plowed, harrowed, and graded. It was kept relatively free of weeds by 
 frequent cultivation. In September, in order to have established turf 
 available for treatment the following spring, a mixture of grasses and 
 clover was sown at the rate of 190 pounds per acre by means of a 10-foot 
 tractor-drawn spreader to a strip 330 feet long and 100 feet wide on the 
 southerly side of the area. This mixture, recommended by the New 
 Jersey Agricultural Experiment Station, contained 45 percent of Kentucky 
 blue grass, 25 percent of redtop, 10 percent of Colonial bent, 15 percent 
 of rye grass, and 5 percent of white clover. After the seed was sown, 
 the ground was rolled lightly to compact the soil and stimulate germina- 
 tion. A deficiency of rain that fall was not favorable to the new grass, 
 but by the spring of 1948 the turf was well established and ready for 
 application of insecticides. 
 
 The problem was how to lay out the experimental plots so that the 
 spreader could be used to apply the insecticides in the same manner as 
 used in commercial nurseries and on large turf areas. Accordingly, 
 the field, including both turf and cultivated portion, was divided into 
 11 strips, each 30 feet wide and extending northward 340 feet. 
 
 By trial and error over a distance of 435 feet, the spreader was 
 adjusted to deliver approximately 250 pounds of 10-percent DDT or 200 
 pounds of 5-percent chlordane per acre. The DDT dust was applied 
 once to strips 1 and 7 and twice to strips 2 and 8; the chlordane dust 
 was applied once to strips 4 and 10 and twice to strips 5 and 11. Strips 
 3 and 9 were left untreated as checks, and strip 6 was left untreated to 
 serve as a barrier between the replicated plots. The pattern of each 
 application was in the form of parallel ribbons of material, about 2 
 inches apart, across the field. When two applications were made these 
 ribbons tended to merge. It appeared that a uniform distribution was 
 obtained with all treatments. 
 
 With each application the amount of dust put into the hopper was 
 recorded, and when the operation was completed the material remaining 
 in the hopper was removed and weighed. The amount of toxicant applied 
 in each treatment was calculated and expressed as pounds per acre. It 
 was found that the equivalent of 25 pounds of DDT per acre had been 
 applied to strips 1 and 7, and of 60 pounds per acre to strips 2 and 8. 
 The equivalent of 10 pounds of chlordane per acre had been applied to 
 strips 4 and 10 and of 19 pounds per acre to strips 5 and 11. The toxi- 
 cants applied to established turf were left on the surface of the ground; 
 in the cultivated area the toxicants were mixed immediately by cultiva- 
 tion with the upper 3 inches of the soil. 
 
 The arrangement provided for duplicate plots, each 30 by 100 feet, 
 on turf and for two pairs of plots, each 30 by 40 feet, for each treat- 
 ment in the cultivated areas. These plots are referred to as A, B, C, 
 and D in the tables. It seemed to be the only arrangement possible for 
 
- 3- 
 
 use with the tractor-drawn equipment, but it had the disadvantage that 
 without randomization of the treatments proper compensation could not 
 be made for variations in the soil throughout the plots. It is believed, 
 however, that from a practical viewpoint this experimental design was 
 adequate to determine whether these treatments had any serious effect 
 on the crops. 
 
 Planting and Rotation of Crops 
 
 The rye, soybeans, and corn were each planted in two adjacent strips, 
 each 40 feet wide, extending across the strips of the treatments described 
 previously. The adjacent strips of a crop were separated by a noncount 
 row, or swath. The seed bed was prepared for each crop by disking to 
 a depth of 3 inches to avoid distributing the toxicants mechanically to a 
 lower level. 
 
 Spring rye, a grain-producing type not so tall or so plump as the 
 common winter rye, was broadcast at the rate of 100 pounds per acre 
 on April 19, 1948, April 12, 1949, and May 11, 1950. In 1948 and 1949 
 good stands were obtained, but in 1950 the planting was so delayed by the 
 cold wet spring that the crop was a failure. It was decided to use the 
 common winter rye in 1951. This seed was sown on October 10, 1950, 
 and a good stand v/as obtained. 
 
 Soybeans of the Black Wilson type were broadcast at the rate of 2 
 bushels per acre on May 10, 1948. A good stand was obtained, but so 
 many weeds developed that the crop could not be harvested in a satis- 
 factory manner. Thereafter the soybeans were sown in rows 36 inches 
 apart, the seed about 3 inches apart in the rows, so that the plants could 
 be cultivated. Twenty-five rows, including the middle barrier row, were 
 sown on May 12, 1949, June 6, 1950, and June 4, 1951. 
 
 The hybrid field corn, Funk G-94, was planted in rows 42 inches 
 apart, the seed about 15 inches apart in the rows. Twenty-one rows, 
 including the middle barrier row, were sown on May 10, 1948, May 13, 
 1949, June 6, 1950, and June 4, 1951. 
 
 The rotation of these field crops was rye, soybeans, corn, and rye, 
 so that, except for the first and the fourth years, each crop was planted 
 in a different strip across the treated plots. 
 
 Soil- Fertility Program 
 
 Although sassafras sandy loam is one of the important agricultural 
 soils, it is necessary to add organic matter, lime, and commercial 
 fertilizers to grow crops or grass in a satisfactory manner. The organic 
 matter in the cultivated area has been built up gradually during the 4 
 years by shredding and disking the crops into the soil and by incorpo- 
 rating a cover crop into the soil in the spring. Rye grass was used as 
 the cover crop over the winter of 1948-49, but because of the difficulty 
 
- 4- 
 
 of killing this crop and mixing it with the upper 3 inches of soil by disking, 
 the use of rye grass was discontinued. Winter wheat was found to be more 
 satisfactory under these conditions. 
 
 Each spring lime was applied to the established turf and to the culti- 
 vated area. In 1948 hydrated lime was used at the rate of 800 pounds per 
 acre. In subsequent years ground limestone was used, 500 pounds per 
 acre in 1949, 1,000 pounds in 1950, and 800 pounds in 1951. With this 
 program of liming, the pH of the soil was maintained between 6.0 and 6.5. 
 
 A commercial 5-10-10 fertilizer was applied twice each year, the 
 first treatment in the spring to the turf and cultivated area, and the 
 second later in the season as a side-dressing to the corn and soybeans 
 in the following amounts: 
 
 Pounds per acre 
 Spring Later in season 
 
 1948 1,000 500 (corn only) 
 
 1949 600 250 
 
 1950 and 1951 500 250 
 
 Harvesting of Crops 
 
 When the rye had made full growth and the heads were maturing, the 
 plants were cut at the surface of the ground in 4-foot swaths with a 
 tractor-powered sickle bar. The swaths in each plot were collected and 
 weighed. Then the cuttings were spread over the plot and disked into the 
 soil. 
 
 The soybeans were cut at the surface of the ground when they had 
 made good growth and the pods had formed. Each 30 -foot row in each 
 plot was cut and weighed. These cuttings were then spread over the 
 plot and incorporated into the soil. 
 
 The weight of the husked ears of corn was used for comparison between 
 plots. When the corn matured, late in September or early in October, the 
 ears were removed, husked, counted, and weighed. The stalks were then 
 shredded and incorporated into the soil. 
 
 Periodically as required the grass on the turf plots was mowed with 
 a power mower and the clippings were left on the ground. During June 
 of each year, when the turf was in its best condition, the grass was cut 
 and the clippings were collected by means of an 18-inch hand mower 
 equipped with a grass catcher. The clippings were then weighed. 
 
 Discussion of Results 
 
 The green weights of the rye, soybeans, grass, and of the mature 
 ears of husked corn in the plots to which the different treatments had 
 been applied are summarized in tables 1 and 2. 
 
- 5- 
 
 In 1948 the rye in all plots germinated normally but the seedlings in 
 the plots treated with DDT had an abnormal purple color. Although this 
 color gradually disappeared, the growth of the rye was visibly retarded. 
 At harvest it was evident that the application of DDT to the soil had 
 definitely reduced the green weight of the crop. In 1949 and 1951, although 
 some discoloration and retardation of the seedlings were evident, there 
 was nothing to indicate that the application of DDT up to 60 pounds per 
 acre had modified the green weight at harvest. During the 4 years there 
 was nothing to indicate that applications of chlordane up to 19 pounds per 
 acre had any detrimental effect on the growth of the rye. 
 
 The application of DDT at rates up to 60 pounds per acre and of 
 chlordane at rates up to 19 pounds per acre appeared to have no signifi- 
 cant effect on the growth of soybeans, corn, or mixed grasses. 
 
 This experiment should not be considered as a study of the photo- 
 toxicity of these insecticides to these plants. As the chemical analyses 
 of the soil-2 showed that practically all the DDT and chlordane had re- 
 mained within the upper 3 inches during the 4 years following the appli- 
 cation, it would be expected that when the roots penetrated below this 
 layer the plants would grow fairly normally. 
 
 Summary 
 
 DDT or chlordane mixed with the upper 3 inches of soil is authorized 
 for the treatment of beds and plots in commercial nurseries that are 
 quarantined because of the Japanese beetle ( Popillia japonica Newm.). 
 Applied to the surface, these toxicants are recommended also for the 
 protection of turf from damage by this insect. 
 
 A 4-year study was made of the effect of these toxicants applied in 
 this manner on growth of grass, rye, soybeans, and corn. The green 
 weights of the crops in the treated plots were compared with the weights 
 in the untreated plots. It was found that, except for a retardation in the 
 growth of rye with DDT the first year, the application of DDT up to 60 
 pounds per acre, or of chlordane up to 19 pounds per acre, had no detri- 
 mental effect on these crops. Since the roots of these plants penetrated 
 below the treated layer of soil, this experiment should be considered as 
 a study of the reactions of crops under this special condition rather than 
 a general study of the phytotoxicity of DDT and chlordane to these crops. 
 
 4/ These analyses were made by R. D. Chisholm and L. Koblitsky, 
 of the Division of Insecticide Investigations. 
 
-6 - 
 
 Table 1. --Effect of applying DDT for control of Japanese beetle larvae 
 on green weight of rye, soybeans, corn, and grass 
 
 Crop 
 
 Year 
 
 Pounds 
 
 DDT 
 per acre 
 
 Green weight in pounds per plot 
 
 Plot A 
 
 Plot B 
 
 Plot C 
 
 Plot D 
 
 Average 
 
 Rye 
 
 1948 
 
 25 
 
 60 
 
 None 
 
 
 1949 
 
 25 
 
 60 
 None 
 
 
 1951 
 
 25 
 
 60 
 None 
 
 Soybeans 
 
 1949 
 
 25 
 
 60 
 
 None 
 
 
 1950 
 
 25 
 60 
 
 None 
 
 
 1951 
 
 25 
 
 60 
 
 None 
 
 Corn 
 
 1948 
 
 25 
 
 (ears) 
 
 
 60 
 
 None 
 
 
 1949 
 
 25 
 
 60 
 None 
 
 
 1950 
 
 25 
 
 60 
 
 None 
 
 
 1951 
 
 25 
 60 
 
 None 
 
 42 
 
 40 
 
 42 
 
 40 
 
 41.0 
 
 24 
 
 29 
 
 34 
 
 29 
 
 29.0 
 
 85 
 
 72 
 
 84 
 
 68 
 
 77.3 
 
 173 
 
 223 
 
 167 
 
 152 
 
 178.8 
 
 223 
 
 221 
 
 165 
 
 150 
 
 189.8 
 
 210 
 
 229 
 
 191 
 
 172 
 
 200.5 
 
 146 
 
 91 
 
 106 
 
 97 
 
 110.0 
 
 130 
 
 85 
 
 76 
 
 81 
 
 93.0 
 
 124 
 
 121 
 
 91 
 
 91 
 
 106.8 
 
 262 
 
 297 
 
 237 
 
 254 
 
 262.5 
 
 281 
 
 297 
 
 234 
 
 207 
 
 254.8 
 
 291 
 
 295 
 
 260 
 
 251 
 
 274.3 
 
 194 
 
 217 
 
 194 
 
 197 
 
 200.5 
 
 205 
 
 194 
 
 200 
 
 202 
 
 200.3 
 
 223 
 
 221 
 
 210 
 
 202 
 
 214.0 
 
 135 
 
 180 
 
 164 
 
 192 
 
 167.8 
 
 125 
 
 156 
 
 109 
 
 164 
 
 138.5 
 
 113 
 
 177 
 
 130 
 
 177 
 
 149.3 
 
 225 
 
 232 
 
 199 
 
 222 
 
 219.5 
 
 252 
 
 245 
 
 219 
 
 221 
 
 234.3 
 
 230 
 
 226 
 
 185 
 
 236 
 
 219.3 
 
 139 
 
 138 
 
 136 
 
 152 
 
 141.3 
 
 124 
 
 143 
 
 117 
 
 153 
 
 134.3 
 
 111 
 
 124 
 
 124 
 
 142 
 
 125.3 
 
 185 
 
 168 
 
 169 
 
 168 
 
 172.5 
 
 195 
 
 184 
 
 169 
 
 156 
 
 176.0 
 
 191 
 
 189 
 
 180 
 
 160 
 
 180.0 
 
 129 
 
 189 
 
 128 
 
 132 
 
 144.5 
 
 183 
 
 200 
 
 140 
 
 145 
 
 167.0 
 
 208 
 
 207 
 
 130 
 
 172 
 
 179.3 
 
Table 1. — (Continued) 
 
 -7 
 
 Crop 
 
 Year 
 
 Pounds 
 
 DDT 
 per acre 
 
 Green weight in pounds per plot 
 
 Plot A 
 
 Plot B 
 
 Plot C 
 
 Plot D 
 
 Average 
 
 Grass 
 
 1948 
 
 1949 
 
 1950 
 
 1951 
 
 25 
 
 76 
 
 60 
 
 87 
 
 None 
 
 60 
 
 25 
 
 80 
 
 60 
 
 98 
 
 None 
 
 80 
 
 25 
 
 34 
 
 60 
 
 41 
 
 None 
 
 31 
 
 25 
 
 75 
 
 60 
 
 73 
 
 None 
 
 84 
 
 95 
 89 
 78 
 
 68 
 65 
 40 
 
 36 
 36 
 32 
 
 79 
 73 
 75 
 
 85.5 
 88.0 
 69.0 
 
 74.0 
 81.5 
 60.0 
 
 35.0 
 38.5 
 31.5 
 
 77.0 
 73.0 
 79.5 
 
-8 - 
 
 Table 2. --Effect of applying chlordane for control of Japanese beetle 
 larvae on green weight of rye, soybeans, corn, and grass 
 
 Crop 
 
 Year 
 
 Pounds 
 
 chlordane 
 
 per acre 
 
 Green weight in pounds per plot 
 
 Plot A 
 
 Plot B 
 
 Plot C 
 
 Plot D 
 
 Average 
 
 Rye 
 
 1948 
 
 11 
 
 19 
 
 None 
 
 
 1949 
 
 11 
 
 19 
 
 None 
 
 
 1951 
 
 11 
 
 19 
 
 None 
 
 Soybeans 
 
 1949 
 
 11 
 
 19 
 
 None 
 
 
 1950 
 
 11 
 
 19 
 
 None 
 
 
 1951 
 
 11 
 
 19 
 
 None 
 
 Corn 
 
 1948 
 
 11 
 
 (ears) 
 
 
 19 
 None 
 
 
 1949 
 
 11 
 19 
 None 
 
 
 1950 
 
 11 
 
 19 
 
 None 
 
 
 1951 
 
 11 
 19 
 None 
 
 74 
 
 79 
 
 82 
 
 62 
 
 74.3 
 
 69 
 
 64 
 
 74 
 
 64 
 
 67.8 
 
 85 
 
 72 
 
 84 
 
 68 
 
 77.3 
 
 207 
 
 211 
 
 173 
 
 163 
 
 188.5 
 
 172 
 
 175 
 
 178 
 
 181 
 
 176.5 
 
 210 
 
 229 
 
 191 
 
 172 
 
 200.5 
 
 103 
 
 147 
 
 96 
 
 103 
 
 112.3 
 
 147 
 
 140 
 
 92 
 
 118 
 
 124.3 
 
 124 
 
 121 
 
 91 
 
 91 
 
 106.8 
 
 285 
 
 306 
 
 280 
 
 276 
 
 286.8 
 
 312 
 
 345 
 
 269 
 
 312 
 
 309.5 
 
 291 
 
 295 
 
 260 
 
 251 
 
 274.3 
 
 236 
 
 199 
 
 198 
 
 196 
 
 207.3 
 
 205 
 
 211 
 
 211 
 
 210 
 
 209.3 
 
 223 
 
 221 
 
 210 
 
 202 
 
 214.0 
 
 133 
 
 137 
 
 144 
 
 165 
 
 144.8 
 
 164 
 
 175 
 
 155 
 
 168 
 
 165.5 
 
 113 
 
 177 
 
 130 
 
 177 
 
 149.3 
 
 216 
 
 238 
 
 173 
 
 246 
 
 218.3 
 
 208 
 
 237 
 
 185 
 
 233 
 
 215.8 
 
 230 
 
 226 
 
 185 
 
 236 
 
 219.3 
 
 126 
 
 106 
 
 149 
 
 142 
 
 130.8 
 
 132 
 
 116 
 
 149 
 
 144 
 
 135.3 
 
 111 
 
 124 
 
 124 
 
 142 
 
 125.3 
 
 192 
 
 193 
 
 184 
 
 170 
 
 184.8 
 
 198 
 
 206 
 
 190 
 
 194 
 
 197.0 
 
 191 
 
 189 
 
 180 
 
 160 
 
 180.0 
 
 141 
 
 173 
 
 110 
 
 153 
 
 144.3 
 
 130 
 
 137 
 
 120 
 
 174 
 
 140.3 
 
 208 
 
 207 
 
 130 
 
 172 
 
 179.3 
 
9 - 
 
 Table 2. --(Continued) 
 
 Crop 
 
 Year 
 
 Pounds 
 
 chlordane 
 
 per acre 
 
 Green weight in pounds per plot 
 
 Plot A 
 
 Plot B 
 
 Plot C 
 
 Plot D 
 
 Average 
 
 Grass 
 
 1948 
 
 1949 
 
 1950 
 
 1951 
 
 11 
 
 66 
 
 19 
 
 74 
 
 None 
 
 60 
 
 11 
 
 63 
 
 19 
 
 61 
 
 None 
 
 80 
 
 11 
 
 38 
 
 19 
 
 41 
 
 None 
 
 31 
 
 11 
 
 80 
 
 19 
 
 72 
 
 None 
 
 84 
 
 86 
 93 
 78 
 
 32 
 26 
 40 
 
 32 
 24 
 32 
 
 82 
 
 74 
 75 
 
 76.0 
 83.5 
 69.0 
 
 47.5 
 43.5 
 60.0 
 
 35.0 
 32.5 
 31.5 
 
 81.5 
 73.0 
 79.5 
 
UNIVERSITY OF FLORIDA 
 I I I I II III III 
 
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