Foliar Insecticide Applications Research Articles

Control of Aphids, 1988:

Abstract Foliar and systemic experiments were randomized complete block designs with 6 replicates each conducted at Presque Isle, Maine, on land that was in clover in 1987. The planting dates were 19 May for the systemic experiment and 20 May for the foliar experiment. In the foliar experiment the 3.0-m space between blocks and the 1.4-m space between columns and at the sides and ends of the experiments were sown to oats after planting. Each replicate consisted of 4 rows of potatoes, each row 0.9 m apart and 15.0 m long. The healthy Katahdin seed pieces (75 g each) were planted with a tractor-pulled, assisted-feed planter. Fertilizer and hilling practices were normal for the area. Late blight was controlled by 6 foliar applications ofDithane FZ (2338 ml/ha the weeks of 11 and 18 Jul, 2806 ml/ha the weeks of 25 Jul and 1, 8, and 15 Aug). Sidedress applications of insecticides were made by hand with a plastic tube applying previously weighed amounts of insecticide. Foliar insecticide applications were made with a Century boom sprayer, 3 nozzles per row at 6.3 kg/cm2 pressure and 0.94 kl/ha. The number of aphids (by species) was counted on top, middle, and bottom leaves of 25 plants in the middle rows of each plot. When dates of count and application were the same, aphid counts were made prior to applications of the insecticide. Analyses of variance were calculated following transformation of the data using log10(x + 1). Means of the total number of wingless aphids were compared using DMRT and then reconverted. The soil was classified as Caribou loam, pH 5.2. Total monthly rainfall for Jun, Jul, and Aug was 3.7, 8.3, and 13.7 cm, respectively. The average temperature for each of the same 3 months was 15.7, 20.4, and 18.9°C.

Irish Potato, Control of Colorado Potato Beetle, 1987

Abstract The experiments were randomized complete block designs with 6 replicates. Experiment CPB-A was planted 8 May, and experiments CPB-B and CPB-C were planted 11 May at Presque Isle, Maine, on land that was in clover in 1986. The 3.0-m space between blocks was bare soil and the 4-row plots were separated by 2 rows of untreated potatoes. All rows were planted with an assisted-feed planter 0.9 m apart and 15.0 m long, and the healthy seed pieces (75 g) were 30 cm apart. Fertilization and hilling practices were normal for the area. Late blight was controlled by 7 foliar applications of Dithane F-45 (2338 ml/ha the weeks of 6, 13, and 20 Jul; 2806 ml/ha the weeks of 27 Jul and 3, 10, and 17 Aug). Foliar insecticide applications were made with a Century boom sprayer, 3 nozzles/row at 7.0 kg/cm2 pressure and 1.2 kl/ha. Numbers of larvae and adults were counted on 25 whole plants in the middle rows of each plot. When dates of count and application were the same, beetle counts were made prior to application of insecticides. Analyses of variance were calculated following transformations of data using log10(x + 1). Means of the sum of larvae and adult beetles were compared using DMRT and then reconverted. The soil was classified as Caribou Loam, pH 5.2. Total monthly rainfall for June, July, and August was 8.8, 7.6, and 4.4 cm, respectively. The average temperature for each of the same 3 months was 16.5, 19.0, and 19.1°C.

Irish Potato, Control of Potato Infesting Aphids, 1987

Abstract The experiments with fohar and systemic insecticides were randomized complete block designs with 6 replicates each and were conducted at Presque Isle, Maine, on land that was in clover in 1986. The potato planting dates were 20 May for the systemic insecticide experiment and 18 May for the foliar insecticide experiment. In each experiment the 3.0-m space between blocks and the 1.4-m space between columns and at the sides and ends of the experiments was sown to oats after planting. Each plot consisted of 4 rows of potatoes, each row 0.9 m apart and 15.0 m long. The healthy Katahdin seed pieces (75 g each) were planted with a tractor-pulled, assisted-feed planter. Fertilizer and hilling practices were normal for the area. Late blight was controlled by 7 foliar applications of Dithane F-45 (2338 ml/ha the weeks of 6 and 13 Jul; 2806 ml/ha the weeks of 20 and 27 Jul and 3, 10, and 17 Aug). Side-dress applications of insecticides were made by hand with a plastic tube applying previously weighed amounts of insecticide. Measured amounts of insecticide were applied on each seedpiece for the seedpiece treatments. Foliar insecticide applications were made with a Century boom sprayer, 3 nozzles/row at 7.0 kg/cm2 pressure and 0.95 kl/ha. Numbers of aphids (by species) were counted on top, middle, and bottom leaves of 25 plants in the middle rows of each plot. When dates of count and application were the same, aphid counts were made prior to applications of the insecticide. Analyses of variance were calculated following transformation of the data using logI0(i + 1). Means of the total number of wingless aphids were compared using DMRT and then reconverted. The soil was classified as Caribou loam, pH 5.2. Total monthly rainfall for June, July, and August was 8.8, 7.6, and 4.4 cm, respectively. The average temperature for each of the same 3 months was 16.5, 19.0 and 19.1°C.

Irish Potato, Control of Potato Infesting Aphids, 1986

Abstract The foliar and systemic experiments were randomized complete block designs with 6 replicates each and were conducted at Presque Isle, Maine, on land that was in clover in 1985. The planting dates were 3 Jun for the systemic experiment and 27 May for the foliar experiment. In each experiment the 3.0-m space between blocks and the 1.4-m space between columns and at the sides and ends of the experiments were sown to oats after planting. Each plot consisted of 4 rows of potatoes, each row 0.9 m apart and 15.0 m long. The healthy Katahdin seed pieces (75 g each) were planted with a tractor-pulled, assisted-feed planter. Fertilizer and hilling practices were normal for the area. Late blight was controlled by 7 foliar applications of Dithane M-45 (1681 g/ha on 14, 21, and 28 Jul; 2242 g/ha on 4, 11, 18, and 25 Aug). Side-dress applications of insecticides were made by hand with a plastic tube applying previously weighed amounts of insecticide. Measured amounts of insecticide were applied on each seed-piece for the seed-piece treatments. Foliar insecticide applications were made with a Century boom sprayer, 3 nozzles/row at 7.0 kg/cm2 pressure and 1.2 kl/ha. Numbers of aphids (by species) were counted on top, middle, and bottom leaves of 25 plants in the middle rows of each plot. When dates of count and application were the same, aphid counts were made prior to applications of the insecticide. Analyses of variance were calculated following transformation of the data using log10(i + 1). Means of the total number of wingless aphids were compared using DMRT and then reconverted. The soil was classified as Caribou loam, pH 5.2. Total monthly rainfall for June, July, and August was 5.5, 10.5, and 12.6 cm, respectively. The average temperature for each of the same months was 14.5, 17.8, and 17.2°C.

Irish Potato, Control of Colorado Potato Beetle, 1986

Abstract The experiments were randomized complete block designs with 6 replicates. The south and north experiments were planted 27 and 29 May, respectively, at Presque Isle, Maine, on land that was in clover in 1985. The 3.0-m space between blocks was bare soil and the 4-row plots were separated by 2 rows of untreated potatoes. All rows were planted with an assisted-feed planter 0.9 m apart and 15.0 m long, and the healthy seed pieces (75 g) were 30 cm apart. Fertilization and hilling practices were normal for the area. Late blight was controlled by 8 foliar applications of Dithane M-45 (1681 g/ha on 7, 14, 21, and 28 Jul; 2242 g/ha on 4, 11, 18, and 25 Aug). Foliar insecticide applications were made with a Century boom sprayer, 3 nozzles per row at 7.0 kg/cm2 pressure and 1.2 kl/ha. Numbers of larvae and adults were counted on 25 whole plants in the middle rows of each plot. When dates of count and application were the same, beetle counts were made prior to application of insecticides. Analyses of variance were calculated following transformations of data using log10(x + 1). Means of the sum of larvae and adult beetles were compared using Duncan's new multiple range test and then reconverted. The soil was classified as Caribou loam, pH 5.2. Total monthly rainfall for June, July, and August was 5.5, 10.5, and 12.6 cm, respectively. The average temperature for each of the same 3 months was 14.5, 17.8 and 17.2°C. Approximately 25 over-wintered adult beetles were added to each plot in June to supplement the natural population.

Evaluation of At-Planting and Foliar Insecticide Applications for Control of Early-Season Pests in Cotton, 1987

Abstract A small-plot field study was conducted at the Texas A&M Univeristy Research and Extension Center at Corpus Christi to evaluate soil and foliar insecticides for control of early-season pests in dryland cotton. Four treatments and an untreated check were compared in 4-row × 30-ft plots of cotton planted 19 Mar on 38-inch rows. Treatments were replicated 3 times in a randomized complete block design. Using Gandy applicator boxes, soil insecticides (Counter and Temik) were applied in the seed furrow at planting time. Applications of the foliar insecticide treatment (Cygon) were initiated at the pinhead square stage of cotton growth on 8 May; subsequent applications were made on 14, 21, and 28 May. Cygon applications were made with a CO2-pressurized (35 psi) backpack sprayer, calibrated to deliver 4.5 gal total spray/acre through 2 size 3X hollow-cone nozzles/row. Edaphic conditions at planting time consisted of 15% water (by weight) in top 4 inches of soil and a temperature of 67°F at 4 inches below surface of soil. The soil type was Victoria clay with an organic matter content of 1.7%. Following planting, rainfall did not occur at the test site until 4 Apr (1.0 inch). Accumulated rainfall at the test site from planting date to first bloom stage of cotton growth (the period during which data on pest infestations were gathered) was 5.8 inches. A light freeze (31°F for 1 hr) occurred 31 Mar. Also, the test site was subjected to heavy rainfall (12 inches) and flooding during the first 2 wk in June; fruit-shed by plants during this period was extensive. Efficacy of treatments was evaluated by inspecting terminals of 20 randomly chosen plants in each plot for numers of fleahopper nymphs and thrips and by inspecting terminal leaves (third leaf from apex of plant) of 20 randomly chosen plants in each plot for numbers of aphids and adult female mites. A plant count was taken at the third leaf stage of cotton growth to determine whether the soil insecticides had an effect on the development of a stand. Seed cotton was hand-harvested from 13.6-ft section of row in each plot for yield analysis.

Cabbage Root Aphid Control 1986

Abstract 'Sanibel' variety cabbage was planted 7 Oct into double-row beds with 40-inch centers at the Hoblitzelle Research and Demonstration Farm, Mercedes, Tex. Soil type was an Hidalgo sandy clay loam. Plants were thinned to a 6-inch spacing on 1 Nov, and 60 lb N-32 fertilizer was side-dressed on 3 Dec. Two separate experiments were conducted, one to evaluate efficacy of foliar-applied insecticides, and one to evaluate side-dressed insecticides for control of poplar petiole gall aphids (cabbage root aphids). Experimental design for both tests was a randomized complete block with 4 replications. The plots measured 2 beds by 30 ft (foliar test) or 4 beds by 30 ft (side-dress test) with a buffer row between plots. Side-dress treatments were applied on 3 Dec, and foliar sprays were begun 24 Dec. The RH-7988-treated plot received 1 foliar application, the other 2 insecticides were sprayed twice at a 7-day interval. Soil injections were applied with a liquid fertilizer applicator, and foliar sprays were discharged through a COzpowered, backpack sprayer calibrated to spray 10 gal/acre (30 psi, 4 flat-fan nozzles per plot). Efficacy was evaluated by removing the roots of 4 plants from each plot and washing them in 1 gal of water containing 1 tablespoon of CaCl. Dislodged aphids were counted as they floated to the surface of the water. Cabbage heads were harvested on 13 ft, 2 inches of row per plot to determine yield. Data were analyzed for treatment differences with ANOVA, and means were separated with Duncan's New Multiple Range Test.

Aphid Control on Wheat in the Spring with Foliar Applied Insecticides, 1986

Abstract Seven insecticides were evaluated as late spring applications to determine their effect on grain aphids and grain yield. Plots were planted on 27 Sep ‘85 using a tractor-mounted 4-row belt-cone Almaco grain drill with double disc openers. Seeding rate was 40 lb/acre. Plots were furrow-irrigated in the spring. Applications were made at milk and soft dough stages of wheat on 3 Jun (Capture and Lorsban only) and 12 Jun ‘86 (Capture excluded), respectively, using a CO2 plot sprayer mounted on a bicycle-wheeled carriage. Sprayer output was 58 gal/acre at 40 psi. Plots were 4 rows (12 inches between rows) by 17 ft in length, replicated 4 times in a randomized complete block design. Aphid control was determined on the basis of Berlese-Tullgren funnel aphid extractions (6 plants/plot/posttreatment sample). Plots were harvested 21 Jul ‘86 with a Hege Combine.

Aphid Control on Spring Wheat with Foliar Applied Insecticides, 1986

Abstract Owens’ wheat was planted on 23 Apr at the University of Idaho Research and Extension Center, Caldwell, ID in a furrow-irrigated field. Plots were 12 ft by 6 ft in a randomized complete block design with 6 replicates. A 4 ft untreated border was between plots and 6 ft of fallow ground separated blocks. All treatments were applied using a CO pressurized hand sprayer delivering 38 gal water/acre at 35 psi. Capture 2EC at 0.8 lb (AI)/acre was applied on 14 and 20 Jun and 8 Jul to keep a treatment relatively free of aphids. Capture was also applied to one plot on 20 Jun at approximately flowering and another plot at early milk stage, 17 Jul. The remaining treatments were applied 8 Jul. Aphid counts were taken 8, 10, 24, and 29 Jul. Plots were harvested 13 Aug with a small-plot combine which cut a 5 ft swath. No phytotoxicity was noted in any of the plots.

Potato Yields with Soil Systemic Plus Foliars and Foliars Alone, 1985

Abstract Two sets of plots on clay soils under dryland conditions (Grand Forks, ND, Crookston, MN) and one set on irrigated sand (Royalton, MN) were established for this trial. Individual plots were 4 rows × 30 ft in length replicated 4 times at each location and treatments were arranged in a randomized complete block. Norchips were grown at Grand Forks and Crookston and Russet Burbanks at Royalton. Four foliar insecticide applications were made at each location on 1, 15 and 30 Jul and 15 Aug. Application was made with a hand held C02 sprayer using about 20 gal total material per acre applied at 40 psi. Three fungicide applications were made at each site and were separate from insecticide applications. Yields were taken from the two center rows of each plot and graded.

Control of E. Hirtipennis and M. Persicae on Burley Tobacco with Foliar Insecticides, 1986

Abstract Eight foliar-applied insecticide treatments were evaluated at the Tobacco Experiment Station, Greeneville. Burley tobacco was transplanted on 6 Jun. Plots were 30 ft × 3 rows spaced 42 inches apart. Plants were spaced 18 inches apart. Four randomized complete blocks were separated by 5 ft alleys. Soil classification was Huntington with 2-5% slope, pH 6.6. Insecticide treatments were applied 3 times during the season (8 Jul, 24 Jul, 7 Aug). Sprays were applied with 2.5 gal compressed CO2 sprayers at 30 gal/acre and tank pressure of 30 psi. Flea beetle damage was evaluated as number of feeding holes/10 leaves; counts were made on the fifth leaf (of width greater than 2 inches) from top of plant. Aphid ratings ranged from 0 (no evident infestation) to 5 (heavy infestation with necrosis of lower leaf basis). Rainfall for the growing season was 9.93 inches with an additional 2 inches of irrigation on 18 Jun. Tobacco was harvested on 19 Sep.

Aphid Control of Late Planted Wheat with Foliar Applied Insecticides, 1985

Abstract ‘Twin’ wheat was planted 26 Apr. at the University of Idaho Research and Extension Center, Caldwell, ID, in a furrow-irrigated field. Plots were 5 ft wide by 20 ft long and each bordered by a 3-ft buffer strip. Treatments were arranged in a randomized complete block design with 5 replications. Sprays were applied with a CO2 pressurized sprayer at 35 psi delivering 40 gal water/acre. Early sprays (2-4 aphids/tiller) were applied 27 Jun. Late milk and dough-stage sprays were applied on 9 and 12 Jul respectively. All other sprays were applied on 3 Jul. Aphids were sampled by examining 10 tillers taken at random through the length of the plot. Plots were counted on 4, 8, 16, and 23 Jul. Plots were harvested and yield taken 27 Aug.

Irish Potato, Control of Colorado Potato Beetle, 1985

Abstract The experiment was a randomized complete block design with 6 replicates, planted 23 May at Presque Isle, ME on land that was in clover in 1984. The 3-m space between blocks was bare soil. The 4-row plots were separated by 2 rows of untreated potatoes. All rows were machine planted 0.9 m apart and 15.0 m long and the healthy seed pieces (ca. 75g) were 30 cm apart. Fertilization and hilling practices were normal for the area. Late blight was controlled by 7 foliar applications of Dithane M-45 (1681 g/ha the weeks of 8 and 15 Jul, 2242 g/ha the weeks of 22, 29 Jul, 12, 19 and 26 Aug) and 1 application of Ridomil 2E (1.17 1/ha 31 Jul). Foliar insecticide applications were made with a Century boom sprayer, 3 nozzles per row at 7.0 kg/cm2 pressure and 1.2 kl/ha. Numbers of larvae and adults were counted on 25 whole plants in the middle rows of each plot. When dates of count and application were the same, beetle counts were made prior to application of insecticides. Analyses of variance were calculated following transformations of the data using log10 (x + 1). Means of the sum of larvae and adult beetles were compared using Duncan’s new multiple range test and then reconverted. The soil was classified as Caribou Loam, pH 5.2. Total monthly rainfall for Jun, Jul, and Aug was respectively 11.2, 13.8, and 6.1 cm. The average temperature for each of the same 3 mo was 15.6, 19.4 and 17.2°C. Approximately 40 overwintered adult beetles were added to each plot on 26 Jun to supplement the natural population.

Irish Potato, Control of Potato Infesting Aphids, 1985

Abstract The foliar and systemic experiments were randomized complete block designs with 6 replicates each and were conducted at Presque Isle, ME on land that was in clover in 1984. The planting dates were 21 May ’85 for the systemic experiment and 22 May, for the foliar experiment. In each experiment the 3-m space between blocks and the 1.4-m space between columns and at the sides and ends of the experiments were sown to oats after planting. Each plot consisted of 4 rows of potatoes 0.9 m apart and 15.0 m long. The healthy Katahdin seed pieces ca. 75 g each were planted with a tractor-pulled, assisted-feed planter. Fertilizer and hilling practices were normal for the area. Late blight was controlled by 7 foliar applications of Dithane M-45 (1681 g/ha weeks of 8 and 15 Jul, 2242 g/ha weeks of 22, 29 Jul, 12, 19 and 26 Aug) and 1 application of Ridomil 2E (1.17 1/ha 31 Jul). Soil applications of insecticides were made with a modified Gandy applicator just prior to planting or as a sidedressing after emergence. Foliar insecticide applications were made with a Century boom sprayer, 3 nozzles per row at 7.0 kg/cm2 pressure and 1.2 kl/ha. Numbers of aphids (by species) were counted on top, middle, and bottom leaves of 25 plants in the middle rows of each plot. When dates of count and application were the same, aphid counts were made prior to applications of the insecticide. Analyses of variance were calculated following transformation of the data using log10(x + 1). Means of the total number of wingless aphids were compared using DMRT and then reconverted. The soil was classified as Caribou Loam, pH 5.2. Total monthly rain fall for Jun, Jul, and Aug was respectively 11.2, 13.8 and 6.1 cm. The average temperature for each of the same 3 months was 15.6, 19.5 and 17.2°C.

Sorghum Greenbug Control, 1980

Abstract These experiments were conducted at the University of Nebraska, South Central Research and Extension Center Farm, Clay Center, NE. Experiment 1 was arranged in a split block design with 10 replications; Experiments 2, 3, and 4 were arranged in a randomized complete block design with 5 replications. Plots were 4 rows (spaced 76-cm) 9.1 m long. The 2 center rows were used for insect counts and yield. In-furrow planting-time application of granules was made by directing the insecticide delivery tube from Noble metering devices into the planter shoe just behind the seed delivery tube. Banded planting-time application of granules was made by directing the granule delivery tube from Noble metering devices to in front of the planter press wheel through an 18-cm bander. Cultivation application of granules was made by directing the insecticide over the plants through the granule delivery tubes from Noble metering devices mounted on the cultivator. Foliar application of liquid insecticides was made with a compressed air plot sprayer mounted on a high-clearance ground sprayer. Drop nozzles were used so that plants received spray from the top and both sides

Foliar Applications of Insecticides for Control of Biotype E Greenbugs on Grain Sorghum, 1985

Abstract This test was conducted at the University of Nebraska Field Laboratory, Mead, NE, in grain sorghum planted 25 May. Plots were 3 rows, 30 ft long. Treatments were replicated 4 times in a randomized complete block design. Insecticides were applied by a bicycle-wheeled plot sprayer at 40 psi and 29.3 gal/acre through a boom fitted with 1 top nozzle and 2 drop nozzles/row. The liquids were propelled with pressurized CO2. Insecticides were applied 23 Jul when plants were in the 10-leaf stage. The efficacy of each insecticide was evaluated by counting live greenbugs on 6 plants selected at random from the center row of each plot at 1, 7, and 14 days posttreatment. Rainfall during the sampling period was measurable in inches on 24 Jul (0.20), 30 Jul (0.50), and 5 Aug (0.40).

Insect Control on Burley Tobacco with Foliar Insecticides, 1985

Abstract Eight foliar-applied insecticide treatments were evaluated at the Tobacco Experiment Station, Greeneville. Burley tobacco Gr 136 was transplanted on 21 May. Plots were 30 ft × 40 rows spaced 40 inches apart and 18 inches within rows. Four randomized complete blocks were separated by 5-ft alleys. Soil was classified as Hermitage silt loam with 2-5% slope, pH 6.0. Four insecticide applications were made during the season (11 Jun, 26 Jun, 18 Jul, 9 Aug). Sprays were applied with 2.5 gal compressed CO2 sprayers at 30 gal/acre and tank pressure of 30 psi. Flea beetle damage was evaluated as average number of feeding hole/10 leaves; counts were made on the fifth leaf (of width greater than 2 inches) from top of plant. Aphid ratings ranged from 0 (no evident infestation) to 5 (heavy infestation with necrosis of lower leaf bases). Hornworm damage was counted on 3 Jul and expressed as % plants damaged.

A Test of Foliar-applied Systemic Insecticides to Prevent Damage to White Spruce Cones by Insects

Cone-bearing portions of white spruce trees were sprayed by means of hydraulic sprayers with 1.0 and 1.5 per cent solutions of dimethoate, methomyl, and acephate in a 12-year-old and a 25-year-old plantation. Cone damage was reduced by insecticides but no differences between the two application rates were detected. In the younger plantation, each insecticide provided highly significant reductions in damage by spruce coneworm, spiral spruce cone maggot, and spruce cone-axis midge, but neither reduced spruce budworm damage; there were no differences among insecticides. In the older plantation, each insecticide provided significant and equal reductions in cone maggot damage; seedmoth and cone-axis midge damage was reduced by dimethoate and methomyl, but not acephate, and no insecticide reduced coneworm damage. Some factors to consider in further testing of these or other insecticides for use against cone-damaging insects on seed trees are discussed.

Effect of Various Soil and Foliar Applied Insecticides on Leafminers in Bell Peppers, 1984

Abstract Pepper seeds were planted 15 Mar on a Willacy fine sandy loam into double-row beds (10 inch rows, 40 inch ceners) at the Texas A&M Research and Extension Center, Weslaco, TX. Plots were 45 ft long by 2 beds wide and bordered by 1 row of forage sorglium. Sixteen treatments were replicated 5 times in a randomized complete block design. Soil treatments were injected as a side-dress application to each row on 15 May using gravity-fed soil injection equipment at a rate of 10 gal/ acre. Foliar treatments were applied weekly beginning 15 May through a CO2 powered, tractor-mounted spray boom at 5.5 gal/acre (4 mph, 45 psi, 2 TX4 hollow cone nozzles/bed). Monitor and Trithion were applied at 10 lb (AI)/acre during the first 4 sprays and at 1 lb (AI)/acre during the last 4 sprays. Spray dates were 1, 8, 15, 21 and 29 Jun and 6, 13 and 20 Jul. Efiicacy was evaluated using 4 methods. (1) Weekly leaf samples were collected from each plot 72 h post-spray (10 leaves/plot) and held in modified 1 pt ice cream cartons for adult emergence. (2) Weekly counts of larvae and pupae were collected from 3 styrofoam pupal trays/plot. (3) Counts of leaf abscission points (LAP) and remaining leaves (RL) were taken from 10 randomly selected plants/plot. Percent leaf drop (PDL) was calculated by the formula LAP/(LAF + RL) X 100. (4) Fruit was collected from 10 randomly selected plants/plot.

Irish Potato, Control of Colorado Potato Beetle, 1984

Abstract The experiment was a randomized complete block design with 6 replicates, planted 23 May at Presque Isle, ME on land that was in clover in 1983. The 3.0-m space between blocks was bare soil. The 4-row plots were separated by 2 rows of untreated potatoes. All rows were machine planted 0.9 in apart and 15.0 m long and the healthy seed pieces (ca. 75g) were 30 cm apart. Fertilization and hilling practices were normal for the area. Late blight was controlled by 8 foliar applications of Diathane M-45 (1681 g/ha the weeks of 9 and 16 Jul, 2242 g/ha the weeks of 23, 30 Jul, 6, 13, 20 and 27 Aug). Foliar insecticide applications were made with a Century boom sprayer, 3 nozzles per row at 7.0 kg/cm2 pressure and 1.2 kl/ha. Numbers of egg masses, larvae, and adults were counted on 25 whole plants in the middle rows of each plot. Analyses of variance were calculated following transformations of the raw data using log10 (x + 1). Means of the sum of each stage of the beetle were compared using Duncan’s new multiple range test and then reconverted. The soil was classified as Caribou Loam, pH 5.2. Total monthly rainfall for Jun, Jul, and Aug was respectively 15.52, 13.74, and 7.26 cm. The average temp for each of the same 3 months was 15.6, 20.0 and 19.7°C.