Untreated Rows Research Articles

Effect of Larval Infestation Timing on Insecticidal Control of European Corn Borer in Minnesota Snap Bean, 1994

Abstract This test was conducted on the University of Minnesota, Rosemount Experiment Station, in snap beans planted 2 Jun. Plots consisted of three 30 ft (9.14 m) rows on 30 inch (0.76 m) centers. Two untreated border rows and 7 ft (2.13 m) alleys separated the plots. Treatments were arranged in a split-plot design with four replications. Insecticide treatments were assigned to whole plots, while infestation timings consisted of single-row sub-plots within each whole plot. Treatments were applied 12 Jul using a moderate-clearance Spirit sprayer with 7 TX-10 hollowcone nozzles delivering 27 gpa (252.5 liter/ha) at 50 psi (3.51 kg/cm2) and 3 mph (4.8 km/hour). Plots were manually infested with ECB using a ‘bazooka’ applicator on 8, 15 and 19 Jul, corresponding to bud stage (72%), bloom (63%), and pod growth stages (75% at 0.5-3 inch length), respectively. On each infestation date, eleven consecutive plants in one row of each whole plot were infested with approximately 75 first-instar ECB larvae/plant. Infestations were designed to evaluate the activity of each material 4-d pretreatment, 3-d posttreatment and 7-d posttreatment. Beans were planted so that peak flowering would occur between the first and second generation ECB flights; feral ECB moth flights during this time were low. All treatments were evaluated 8 Aug by selecting five consecutive plants from the center of each infested row. Total pods, pods with feeding damage, stalk damage, and total ECB larvae were recorded.

Sugarbeet Root Aphid Control in Southern Minnesota, 1994

Abstract This study was conducted in a grower’s field <2 km southeast of Shakopee, MN. Beets were planted 12 May. Plants were thinned once to achieve a uniform stand. Each treatment consisted of three 30 ft rows on 22 inch centers; one untreated row bordered treatments on either side. Treatments were arranged in a randomized complete block design with 4 replications. Each plot was manually infested with SRA adults (or fourth instars) weekly on 8, 15, 22 and 29 Jun, with 6, 10, 10 and 8 aphids/ infestation site/plot, respectively. The same 2 ft section of row near the center of the middle row of each plot was infested each week. All insecticides were applied 30 Jun to all three rows of each plot. Granular insecticides were applied using a Noble applicator in a 7 inch band at the base of both sides of the plants. Liquid materials were applied in a directed spray at the base of the plants using a CO2-pressurized back-pack sprayer calibrated to deliver 50 GPA. All treatments were evaluated 9 Sept by recording the percentage of beets infested with one or more SRA/beet and by using the 0-5 scale root rating system (Hutchison & Campbell 1994, J. Econ. Entomol. 87: 465—175), where 0 = uninfested, and 5 = colonies covering 90-100% of the root surface.

Spider Mites in Rose Plant Fields, Wasco, Ca, 1993

Abstract An evaluation was conducted with AC 303,630 on field-grown roses to be harvested as plants. Avid was included for comparison. Experimental design was a RCB with 6 replications. Blocks were single rows of roses planted 42 inches apart and plants were 6 inches apart within the row. Each plot was a 25 ft length of roses, with a 5 ft buffer between plots in the row. A single guard row separated each of the treated rows, and the entire plot was buffered by at least three untreated rows. Treatments were applied with a CO2 backpack sprayer at 30 psi with a TJ 8002 flat fan nozzle. Water was used at the rate equivalent to 100 gpa. Samples were 20 5-leafiet leaves pei plot taken at weekly intervals, transported to the lab, brushed onto glass plates, and counted in concentric fashion using a template. Data are the meat of replicates, and represent the spider mites counted on one-sixth of the plate. Pre-treatment samples were taken 26 May. Acaricides were applied 2" May under partly cloudy skies with temperature 25°C and wind velocity less than 5 mph.

Onion Thrips Control, 1993

Abstract ‘Spartan Banner 80’ onions were direct seeded on 13 May at the Michigan State University Muck Research Farm, Laingsburg, MI. Plots were 3 ft long non-adjacent sections of single rows (16 inch spacing between rows), separated by 8 untreated rows, with five replications in a randomized complete block arrangement. A natural population of thrips present in the field was augmented with thrips introduced on onion tops from a heavily infested commercial field. For each plot, five onion tops were inverted and placed in close contact with the hearts of the onions for 3 days and removed just prior to spray application. Treatments were applied with a hand-held CO2 sprayer with a flat fan nozzle at 40 psi and 50 gal per acre on 18 Aug. Due to a rain, heavy winds and the stage of the onions, plants had begun to lay down by 26 Aug when post-treatment sampling was done. Five standing plants were randomly selected in each plot and thrips were counted. Data were log transformed before analysis.

Broccoli Insect Control, 1993

Abstract Broccoli was transplanted into a field at the Michigan State University Entomology Research Farm, 14 Jul in single rows 5 m long, 0.5 m apart within the rows, with untreated rows between each plot in a randomized complete block design (4 replications per treatment). Treatments were applied on 10, 16, 23, and 30 Aug (30 gallons per acre, 30 psi, back pack CO2 sprayer, one flat fan nozzle over the row). Plants (3/plot) were sampled for insects on 13, 19, 26 Aug and 3 Sep. Heads (3/plot) were harvested on 7 Sep and examined for insects.

Whitefringed Beetle (WFB) Control in Sweet Potato, 1993

Abstract ‘Cordner’ sweet potatoes were transplanted 26 May in a field near Clanton, AL. The soil was high in organic matter, and soil moisture was low at planting. The field had a history of WFB infestation; WFB larvae were detected in pre-plant soil samples. Plot size was 4 rows (36 inch spacing) by 30 feet; treatment plots were bordered on both sides by 4 untreated rows. Treatments were arranged in a randomized complete block design with 4 replicates. At-planting granular formulations were applied by tractor with a Gandy-type applicator. Pre-plant liquid formulations were broadcast over the soil surface using a backpack sprayer with a five nozzle boom. Spray volume and pressure were 80 gpa and 40 psi, respectively. Broadcast spray treatments were incorporated into the top 6 inches of the soil within 10 minutes of application using a tractor-mounted roto-vator, and plant beds formed immediately thereafter. Granular formulations at root swell were applied over the top of the foliage using a tractor-mounted Gandy applicator. The two middle rows per treatment were harvested on 21 Oct and all sweet potatoes from these rows were counted and visually inspected for soil insect damage.

Prevention of Grape Bud Damage, 1993

Abstract ‘Concord’ vineyards 1 and 2 were located in Lowell, Arkansas. It was a randomized complete block design. Each vineyard was divided into 9 blocks (adjacent rows) bordered by untreated rows. Each block had 3 treatments randomly assigned to 9 to 12-vine plots (4 panels of vines) as follows: untreated; 5 cm wide Envirosafe teflon tape (Envirosafe Solutions Corp., Schuylkill Haven, PA) was carefully wrapped around all vine trunks, 5 trellis posts and the 2 horizontal support wires on either end in each plot from 1 to 2 Apr; and a hand pump sprayer at 40 psi was used to apply a carbaryl solution to runoff on each vine and post on 1 and 12 Apr and 9 Apr in vineyards 1 and 2, respectively. The carbaryl solution was 10.6 ml (1.27 g AI) Sevin XLR per liter of a 0.01% solution of water and the surfactant Triton AG98. Counts were made of the damaged and undamaged buds per treatment plot from 21 to 22 Apr.

European Corn Borer Control with Microbial and Pyrethroid Insecticides on Pre-Tassel Sweet Corn, 1993

Abstract This test was conducted on the University of Minnesota, Rosemount Experiment Station in corn planted 1 Jun. Plots consisted of single rows on 30" centers, 30 ft in length, and separated by untreated border rows and 4 ft alleys between replicates. Treatments were arranged in a randomized complete block design with 4 replications. All plots were infested 27 Jul with approximately 25 neonate larvae/plant; larvae were applied to the whorl using ‘bazooka’ applicators. Plant growth stage at the time of infestation was primarily VI2-V13 and 95% pre-tassel (i.e., green tassel visible within the whorl). A single application of each treatment was made 4 Aug; the majority of larvae were second-instars. A medium-clearance Spirit sprayer was used to apply all materials. Liquid formulations were applied with one TX-10 nozzle/row at 40 psi, for a final spray volume of 30 gal/acre. Granular formulations were applied using a Gandy applicator. For all materials, applicator ground speed averaged 2 mph, wind speed 2 mph and ambient temperature 59°F. All treatments were evaluated 23 Aug by dissecting 5 plants per plot, from the tassel to the soil surface.

High Rate of Asana XL, Selected Insecticides and Microbials for European Corn Borer Control in Minnesota Sweet Corn, 1993

Abstract This test was conducted on the University of Minnesota Southern Experiment Station at Waseca in corn planted 4 Jun. Plots consisted of four 30 ft (9.14 m) rows on 30 inch (0.76 m) centers. Two untreated border rows and 6 ft (1.83 m) alleys separated the plots. Treatments were arranged in a randomized complete block design with four replications. A Hagie highboy sprayer with two flat fan (8002VS) nozzles/ row, delivering 35 gal/acre (327.4 liters/ha) at 33 psi (2.3 kg/cm2) and 2 mph (1.2 km/hr), was used to treat the ear zone of each row. A weekly spray schedule was initiated at 75% silk. Because of wet weather conditions, an 11 day treatment interval resulted between first and second applications. Treatments were applied 12, 23 Aug and 2 Sep. Plots were artificially infested with about 25 neonate ECB larvae/primary ear-leaf on 16 Aug. Treatments were evaluated 9 Sep by randomly selecting 25 ears/plot (100/treatment) and recording total ECB larvae, larval size, location and feeding damage.

Evaluation of Seed Treatments for Thrips Control, 1993

Abstract Insecticides applied in-furrow were evaluated at the Plant Science Research Farm, Mississippi State University, Mississippi State, MS. The trial was planted in an RCBD with 5 replications. Plots were 32 ft long by 4 rows wide (38 inch centers) without untreated buffer rows between plots. The soil type was Marietta sandy loam with 1.22% organic matter, 42.5% sand, 39.2% silt, 18.3% clay, and a pH of 7.4. The trial was planted 7 May under the following conditions: excellent soil moisture, soil temperature 84°F, 37.1% relative humidity and ambient temperature of 86°F. The seeding rate was 200 seed per row. Plots were planted with a Maxemerge planter equipped with Almaco seed cones and belt-cones for seed and granule application. Thrips were collected by cutting 10 plants per plot at their base and placing them into a self-sealing plastic bag for transfer to the laboratory. There the plants were washed with a bleach and soap solution onto gridded filter paper. Counts and initial species identification were made by dissection microscope.

Evaluation of Insecticides for Control of Eastern Grape Leafhopper, 1993

Abstract The experiment was conducted in a 4-yr-old vineyard at the Lake Erie Regional Center for Grape Research and Extension in North East, PA. Treatments were applied to ‘Niagara’ grapes trained to the single curtain (no tie) system. Treatments consisted of four vine plots arranged in a completely random design and replicated 3 times. Each treatment row was separated by an untreated buffer row. Applications were made using an FMC, 50 gallon, three-point hitch sprayer equipped with an FMC, vineyard boom. Treatments were applied at 100 gal/acre with pressure adjusted to 100 psi. The treatments were applied on 19 Aug. Precipitation for Aug and Sep was 2.98 and 4.56 inches, respectively. A pre-treatment count of leafhopper nymphs was taken on 13 Aug. Post-treatment evaluations were conducted 7, 14 and 21 DAT. Evaluations consisted of randomly selecting 10 injured leaves per plot pre-treatment and 20 injured leaves per plot post-treatment and recording the number of leafhopper nymphs.

Evaluation of Gaucho Cotton Seed Treatments for Thrips Control, 1993

Abstract Insecticides applied as seed treatments were evaluated at the Plant Science Research Farm, Mississippi State, MS. A RCBD with 5 replications was used. Plots were 35 ft long × 4 rows wide (38 inch centers) with no untreated buffer rows. The soil type was Marietta Loam with 13.3% organic matter, 47.5% sand, 35.0% silt, 17.3% clay, and a pH of 6.3. The trial was planted 7 May under the following conditions: excellent soil moisture, soil temperature 84°F, 37.1% relative humidity and ambient temperature of 86°F. The seeding rate was 200 seed per row. Plots were planted with a Maxemerge planter equipped with Almaco seed cones and belt-cones for seed and granule application. Liquids were applied by use of a CO2 powered sprayer with a single flat fan nozzle (90015VS) turned to spray mostly into the furrow. Application was at 2 mph, and 39 psi for 10 gal/acre. Band width was 1.75 inches. Because of nonuniform growing conditions within the plot area, plots were not harvested. Plant height (between cotyledonary nodes and the apical meristem) was measured on 3 dates, and stand counts and phytotoxicity ratings were made 20 May.

Controlling Aphids in Georgia Flue-Cured Tobacco with Foliar Insecticides, 1993

Abstract Flue-cured tobacco was transplanted on 9 Apr at the Coastal Plain Experiment Station in Tifton, GA. Production practices were carried out according to Georgia Cooperative Extension Service recommendations. A pre-plant incorporated tank mix of the following was applied; Tillam and Devrinol for weed control, Ridomil for blue mold control, and Nemacur for nematode suppression. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots 3 rows wide (36 inch row spacing) × 20 ft long were arranged in a RCBD with 4 replications. Seven insecticide treatments (plus an untreated check) were applied on 31 May to control an aphid population that averaged around 500 per 3 plants (4 upper leaves). The foliar sprays were applied with a CO2-powered backpack sprayer equipped with three TX-12 nozzles directed over a single row, delivering 30 gpa at 40 psi. Each plot was separated by an untreated border row and a 4 ft alley on each end. The number of live aphids on the 4 uppermost leaves was recorded on plants 3, 4 and 6 on row 2 of each plot prior to application and 3, 7, and 14 DAT. On each sampling date the number of live tobacco budworms also was recorded from 8 plants on row 2 of each plot. On 6 and 12 Jul, 8 plants on row 2 were harvested and yield estimates obtained. Data were subjected to ANOVA and Duncan’s Multiple Range Test

Cage Evaluation of Spray Applications on Cotton for Plantbug Control, 1993

Abstract Eight insecticide treatments were evaluated for efficacy against TPB at the Plant Science Research Farm, Mississippi State, MS. A RCBD with 4 replications was used. Plots were 35 ft long × 2 rows wide (38 inch spacing) separated by 12 untreated buffer rows. Foliar applications were applied 7 Jul at 9:45 a.m. with a high clearance spray tractor at 4 mph and 33 psi and 5 gpa. Temperature, relative humidity and wind speed were 91°F, 63% and 0.2 to 4.0 mph, respectively. Insects were collected the day prior to infestation by sweeping wild flowers (clover) with a sweep net, placing them in a glass enclosure, and collecting the adults with an aspirator. Adults were kept overnight in a glass container with a water wick and snap beans. Plants were infested on 7 Jul and 9 Jul by placing a cloth sleeve over the upper third of the plants, fastening them around the stem at the bottom with a rubber band containing two beads (Ponytail holder) placing 10 live insects on the plant and then closing the sleeve above the terminal with a second ‘ponytail holder’. Plants with cages were cut at 24h and returned to the laboratory where the cages were opened in a glass enclosure and the insects were evaluated for mortality. Those that could not move normally when prodded were considered dead. There were only enough insects for 3 replications for the 9 Jul infestation.

Spoke-Injection of Liquid Insecticides for Corn Rootworm Larval Control in Iowa, 1993

Abstract Spoke-injection of liquid insecticides (100% incorporation), was compared with conventional planting- and cultivation-time applications. Plots were established at Rhodes (silty clay loam) and Nashua (loam). A RCB design, with 4 replications, was used. All treatments were applied to single 50-ft length rows with 30-inch row spacing. Granular insecticide formulations were applied with modified Noble metering units mounted on a 4-row John Deere 7100 planter. Plantingtime liquid formulations were applied with a compressed-air delivery system built directly into the planter; 8003E nozzles delivered 10 gpa at 23 psi. Liquid cultivation-time insecticides were applied with a small-plot bicycle sprayer. Two 8003E nozzles, one on each side of the corn row, were positioned to deliver either a 7, or 15-inch band width around the base of the plants; 10 gpa at 10 psi. Broadcast applications of Furadan 4F were applied to single rows. A boom containing three 8002 nozzles (19-inch centers) delivered 13 gpa at 17 psi. One untreated buffer row was left on each side of each "broadcasted" row. Granular cultivation-time insecticide applications were made with electrically-driven Noble units mounted on the tool bar of a 2-row, rear-mounted cultivator. Plastic tubes, positioned directly in front of the cultivator sweeps, directed the insecticide granules to both sides of the corn row for basal treatments. “Spoke-injection” treatments were applied within several days of planting. The spoked applicator cylinder, mounted behind a small tractor, consisted of a 7-inch high-density polyethylene rod, with a 1.5-inch brass axle. Injection points (0.19-inch diam × 1.3-inch in length) were aligned in 10 rows on the cylinder, for a total of 220 points. A tension spring forced the points into the soil. Flat steel scrapers, positioned between rows of points, kept debris from interfering with the function of the spoke injector. Liquid insecticide was injected to a depth of ca. 1 inch using CO2; 20 gpa at 50 psi. Rootworm larval feeding was evaluated by digging 5 roots from each treatment row and rating them on the Iowa 1-6 scale (1 equal to no damage or only a few minor feeding scars, and a 6 rating equal to 3 or more nodes of roots completely destroyed). To determine treatment differences, data were analyzed using ANOVA and means were separated with Ryan’s Q test (REGWQ).

Onion Maggot Control, 1993

Abstract Onions ‘Golden Cascade’ were seeded at the Brink Farm near Grant Michigan on 4 May in single rows using a vee-belt seeder with a 1-inch wide shoe. Plots were 15 ft long, replicated five times in a randomized complete block arrangement, 12 inches between rows, with untreated buffer rows between each plot. Plots were seeded at 12 seeds per foot, for a total of 180 seeds per plot. There were four seed treatments with Trigard plus three in-furrow insecticide treatments and associated control treatments. Trigard treatments were: a previously tested pellet formulation containing sand, a new pellet containing diatomaceous earth, and a seed coat held on the seed with a thin film coat. Pelleted seed included the fungicide Progrow. Seed film coat treatment and untreated seed included thiram. Lorsban, Dyfonate, and Admire treatments were applied in furrow at planting with thiram-treated seed. Three weeks post-planting, 100 plant sections in each replicate (or the entire replicate if 100 plants were not present) were marked. The number of damaged plants in each 100 plant section were counted weekly from 8 Jun-8 Jul. Final stand counts were made at the end of the season.

European Corn Borer Control in Minnesota Snap Beans, 1993

Abstract This test was conducted on the University of Minnesota, Rosemount Experiment Station, in snapbeans planted 8 Jul. Plots consisted of three 30 ft (9.14 m) rows on 30 inch (0.76 m) centers. Two untreated border rows and 7 ft (2.13 m) alleys separated the plots. Treatments were arranged in a randomized complete block design with 4 replications. Treatments were applied 13 Aug using a moderate-clearance Spirit sprayer with 7 TX-10 hollowcone nozzles delivering 27 gpa (252.5 liters/ha) at 50 psi (3.51 kg/ cm2) and 3 mph (4.8 km/hr). All treatments included the sticker/extender Bond at 0.10 fl oz/gal (0.79 ml/liter). During application, wind speed averaged 4-5 mph (6.4-8.1 km/hr) and the temperature was 72°F (22°C). Plots were artificially infested using a ‘bazooka’ applicator on 10, 16 and 20 Aug. Plants were at 20% bloom, 25% pin-bean (beans ≤ 1 inch) and 95% pod growth stages, respectively. On each infestation date, 15-20 consecutive plants in one row of each plot were infested with approximately 25 first-instar ECB larvae/plant. Infestations were designed to evaluate the activity of each material 3-d pretreatment, 3-d posttreatment and 7-d posttreatment. Feral ECB moth flights during this time were low (18/night/light-trap at peak). All treatments were evaluated 16 Sep by selecting five consecutive plants from the center of each infested row. Total pods, pods with feeding damage and total ECB larvae were recorded. Because of poor survival at the 10 Aug infestation, and high-survival in most treatments for the 20 Aug infestation, data only for the 16 Aug infestation are summarized.

Budworm and Aphid Control in Georgia Flue-Cured Tobacco, 1993

Abstract Flue-cured tobacco, CV K-326’, was transplanted on 6 Apr at the Coastal Plain Experiment Station, Tifton, GA. Production practices were carried out according to Georgia Cooperative Extension Service recommendations. A pre-plant incorporated tank mix of the following was applied: Tillam and Devrinol for weed control, Ridomil for blue mold control, and Nemacur for nematode suppression. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots 3 rows wide (36 inch row spacing) × 20 ft long were arranged in a RCBD with 4 replications. Seven insecticide treatments, plus an untreated control, were applied on 4 weekly intervals in Test 1 beginning on 14 May and continuing until 4 Jun to control tobacco budworms that averaged around 3 worms per 8 plants. The foliar sprays were applied with a CO2-powered backpack sprayer equipped with three TX-12 nozzles directed over a single row, delivering 30.3 gpa at 40 psi. Each plot was separated by an untreated border row and an alley 4 ft wide on each end. The number of live small, medium, and large tobacco budworms per 8 plants on row 2 of each plot was recorded prior to treatment and 4 and 7 DAT. The number of live aphids on the 4 uppermost leaves was recorded on plants 2, 4 and 6 on row 2 of each plot on each sampling date. The number of live thrips was recorded on plant 6 on row 2 of each plot on each sampling date in May, then these counts were discontinued due to low population densities. Budworm damage ratings (% defoliation) also were taken on 14 Jun. Beginning on 1 Jul the lower leaves on 8 plants on row 2 were harvested. A total of 4 harvests (primings) was gathered from each plot and yield estimates and quality ratings were obtained. All data were subjected to ANOVA. In this same field of tobacco additional plots were cut back to 1 ft stalks and all leaves removed on 1 Jul. This tobacco was allowed to regrow (2-3 main suckers per plant). On 14 Jul, 11 insecticide treatments plus an untreated control were applied to plots 3 rows wide × 20 ft long arranged in a RCBD with 4 replications, using application techniques previously described. All treatments were reapplied on 22 Jul. The number of live budworms and hornworms per 8 plants on row 2 of each plot was recorded prior to treatment and 5 and 8 DAT following the 1st applications and 5, 8, and 14 DAT following the second applications. Budworm and hornworm defoliation ratings were obtained on 5 Aug. All data were subjected to ANOVA.

Timing of Insecticides for Sra Management in Southern Minnesota, 1993

Abstract This study was conducted at the University of Minnesota agricultural experiment station at Rosemount in sugarbeets planted 14 May. Treatments were replicated 4 times and arranged in RCBD. Each replicate consisted of 3 treated rows on 30 inch centers measuring 70 ft in length. Treatments were separated by a single untreated row. Granular treatments were applied using a single row Noble applicator delivering a 6-inch band to either side of the base of the plant. Liquid treatments were applied using a single nozzle CO2 backpack sprayer with a flat-fan nozzle delivering 27 gpa in a directed band to the base of the plant, with both sides being treated. Four “pre-infest” treatments were applied 29 Jun, prior to artificial infestation, including Counter 15G, Counter 20CR, AC513858 20G, Knox-Out (2340). The remaining treatments were applied 14 Jul. Plots were infested 7, 21 Jul, 10 and 24 Aug. Plots were infested by placing 8-12 SRA adults and 100-200 nymphs at the base of a single plant in the center row of each treatment, with 1 location for the Jul infestations and 1 location for the Aug infestations, separated by 20 ft. Treatments were harvested 21 Sep and evaluated for percent of beets infested and level of infestation using the following SRA Root Rating Index (0-5): 0 = no aphids nor wax present; 1 = 1 colony, wax (or both) <2.5 cm diam; 2 = 2 or more colonies, wax (or both) <2.5 cm diam each, covering less than 50% of root surface; 3 = 1 or more colonies, wax (or both) >2.5 cm diam each, covering <50% of root surface; 4 = multiple colonies, wax (or both) covering 50 to 95% of root surface; 5 = multiple colonies, wax (or both) covering >95% of root surface. Samples were evaluated for percent sugar and impurities at the Southern Minnesota Sugar Cooperative tare laboratory in Renville, MN.

Spider Mites in Rose Plant Fields, 1988

Abstract Acaricides were compared for efficacy in reducing numbers of mites and mite eggs on field roses. Plots were sampled on 1 Jun, 3 days prior to treatment; pretreatment counts did not significantly differ. Treatments were applied with a CO2 backpack sprayer at 100 psi with hollow cone nozzles. The Avid treatment at 400 gpa was applied with a Solo knapsack sprayer at 32 psi. Treatment design was a RCB with 8 replications. Each plot was 20 ft of row of two adjacent rows (42 inch row spacing) with a 5 ft buffer between plots in the row. Plots were bordered by untreated rows of roses. Twenty leaves per plot were taken at weekly intervals, transported to the lab, brushed onto glass plates, and counted in concentric fashion using a template. Data are the mean of replicates, and represent the mites counted on one-sixth of the plate. Data were (x + 1) transformed to establish homogeneity of variance. Means shown were obtained by back-transforming the data. No phytotoxicity was observed.