Plot Sprayer Research Articles

Alfalfa Insect Control, 1979

Abstract An eight year old stand of alfalfa located at the Newland’s Field Station, Fallon, Nevada was used for this study. Treatments were applied at near full bud stage when 30 - 40% of the plants were showing alfalfa weevil damage. Plots were 25 x 50 ft and arranged in a randomized complete block design with four replicates. Sprays were applied with a CO2 activates plot sprayer calibrated to deliver 17.2 gpa at 30 psi. Treat-ments were made on May 21 ‘79. Post treatment counts were taken on May 24, 28 and Jun 5 and were based on 10 (180 degree) sweeps of a standard net from each rep.

Audible Timer for Hand-Carried Plot Sprayers

We describe a small, light-weight, battery-powered timer that emits an audible signal at 1-s intervals. This audible timer is used to monitor ground speed when applying chemicals to plots, thereby eliminating the need for manual manipulation of a stop watch.

Grasshopper Control, 1979

Abstract Plots were arranged in a randomized complete block design in Clay County, Nebraska. Plots were 20 ft (6 m) wide and 100 ft (30.5 m) long, replicated three times. One end of each plot bordered a bromegrass pasture and the other end bordered a field of grain sorghum. Liquid insecticides were applied with a compressed air plot sprayer mounted on a tractor. Spraying Systems Tee-Jet 8002 nozzle tips were used to apply approximately 17.7 gal (67 L) per acre on Jul 9'79. Sevin baits were hand cast throughout the designated plot area. Grasshopper populations were deter-mined by making two separate sweeps in each plot at each date of observation.

Corn Earworm Control, Prosser, WA, 1978

Abstract Thirteen chemicals at various rates were applied to sweet corn using a “Highboy” high-clearance experimental plot sprayer calibrated to deliver 42 gpa at 50 psi. Plots were 4 rows wide on 34-inch centers, 30-feet in length, replicated 5 times in a randomized complete block design. The two center rows of each plot were sprayed on both sides using TX-3 cone nozzles directed at the ears from above and below. The outside rows of each plot served more as “buffer rows”, i.e., nozzles were directed somewhat downward restricting possible spray drift into adjacent plots. Sprays were applied on Sep 2, 6, 10, 14, 19 and 22. Twenty ears were sampled at random from the center rows of each replicate on Sep 26. Each ear was evaluated for earworm damage, length of feeding damage from eartip, and circumference feeding damage using an index of 0 to 1 where 0 = no feeding, 0.1 = 1 to 2 kernals, 0.2 = eartip up to 1/5 circumference, 0.25 = 1/4, 0.5 = 1/2, 0.75 = 3/4, 1.0 = entire circumference. Additionally, 20 ears/treatment selected at random from two replicates were sampled for fresh corn processing to determine if any chemical treatments affected corn quality, i.e., moisture, color, and soluble solids.

Aphid Control on Spring Wheat, Royal Slope, Washington, 1978

Abstract The study was conducted on a late maturing (kernals milky ripe), irrigated spring wheat. Plots were treated on July 12. Foliar sprays were applied using a compressed air plot sprayer mounted on a bicycle-wheeled carriage, calibrated to deliver 50 gpa at 40 psi. Dyfonate 10G treatments were hand applied by evenly shaking preweighed doses of granules over the plots. Temperature at the time of application was 77°F. Plots were 4 rows wide on 12-inch centers, 20 feet in length, replicated 4 times in a randomized complete block design. On July 14, 20 stems (18 inches in length, head included)/replicate were sampled at random from the center rows. Efficacy was based on total aphids/20 stems. Plots were harvested for yield, August 21.

Spearmint, Alfalfa Looper and Mint Aphid Control, Washington, 1978

Abstract Five insecticides were applied as broadcast sprays on Jun 21, using a compressed air plot sprayer mounted on a bicycle-wheeled carriage, calibrated to deliver 25 gpa at 40 psi.Temperature was 96°F at the time of spraying. Plots were 8 x 17 ft, replicated 3 times in a randomized complete block design. Mint height was 2 to 2.5 ft. Efficacy was based on insects collected with a 15-inch diameter sweep net.

Eppermint, Fumibotys Fumalis Control, Washington, 1978

Abstract An infested 3-year-old peppermint field near Harrah, WA, was selected to study two insecticides for control of Fumibotys fumalis (Lepidoptera: Pyralidae) larvae. F. fumalis is a serious new rhizome-boring soil pest of peppermint in central Washington. Insecticides were applied as broadcast sprays on Sep 28, using a compressed air plot sprayer mounted on a bicycle-wheeled carriage, calibrated to deliver 25 gpa at 40 psi. Soil temperature was 72°F at a depth of 2 inches on the date of spraying. Plots were 8 x 30 ft, replicated 4 times in a randomized complete block design. Following insecticide application, plots were sprinkler irrigated for 12 hours. Mint height was 1 to 2 inches. Soil was classified as an Ashue loam, with a pH of 6.5, percent organic matter 1.4. Efficacy data were based on three 0.5 ft2 soil samples/replicate (soil depth sampled, 3 inches). Samples were placed in Berlese funnels for 48 hours for larval recovery.

Alfalfa Weevil and Pea Aphid Control on Alfalfa in Washington, 1977

Abstract Eight insecticides were evaluated at Badger Basin in Kittitas County. These materials were applied to 8 x 14 ft plots in a randomized complete block design with untreated checks in 3 replications. Sprays were applied on June 7, 3.5 weeks prior to harvest, with a compressed air plot sprayer mounted on a bicycle-wheeled carriage, using 40 psi pressure and applying 32.5 gal/acre. The plots were evaluated on June 16 by taking 25 individual stems of alfalfa from each plot and counting the weevils and aphids present. A 2nd evaluation was taken on June 29 using a sweep net. Pea aphid densities were categorized using a rating scale of 1 to 7 (1 = no aphids, 2 = 1-10, 3 = 10-30, 4 = 30-50, 5 = 50-100, 6 = 100-200, 7 =>200).

Evaluation of Insecticides to Control Scale on Timothy in Washington, 1977

Abstract Eight insecticides were evaluated at Badger Basin in Kittitas County on timothy-alfalfa. Insecticides were applied to 8 x 25 ft plots in a randomized complete block design with untreated checks in 3 replications. Sprays were applied on June 7 with a compressed air plot sprayer mounted on a bicycle-wheeled carriage, using 40 psi pressure and applying 32.5 gal/acre. Timothy height was 2 to 3 ft. The plots were evaluated on June 29 by rating the abundance of scale/ft2 in each plot using a scale of 1 to 6 [1= no crawler or mature scale; 2=no crawlers, a few mature scale (<10); 3=occasional crawler (1 to 2), 10 to 20 mature scale; 4= 2 to 10 crawlers, 10 to 20 mature scale; 5=11 to 50 crawlers, 20 to 50 mature scale; 6=>50 crawlers, > 50 mature scale].

A Portable Sprayer for Treating Experimental Plots

Abstract The construction and operation of a portable light-weight spray boom and accompanying backpack are described. The sprayer can be used to apply pesticides accurately to experimental plots 3 or 4 m wide and is operated by two people. For lightness, both the main framework of the boom, to which the nozzles are attached, and the supporting struts are constructed of aluminium. The pesticide spray is supplied to the boom from a backpack consisting of a stainless steel tank (either 6 or 12 l capacity) and a high pressure gas cylinder. This sprayer has been found to be suitable for application of pesticides to plots larger than those normally treated with most small plot sprayers, but smaller than those requiring vehicle-mounted machines. An appendix lists the suppliers of the parts used and their cost.

Corn Earworm Control, 1976

Abstract Twelve chemicals and microbial treatments at various rates were applied to corn grown under furrow irrigation on the WSU Research Unit at Royal Slope. Experimental plots were four rows × 50 ft long, with 15-ft alleys within rows and one blank row between adjacent treatments, replicated three times in a randomized complete block design. Four applications were made at 4-day intervals beginning Aug 19'76 (10% silk) using a "Highboy" tractor-mounted, high-clearance experimental plot sprayer delivering 50 gal/acre at 40 psi. Weather conditions were normal during the application periods. Ten days after the last application, 25 ears were randomly selected from the two middle rows of each plot. Each sample was checked for number of ears damaged and number of dead and live earworms present. Extent of damage was rated for length of tunnels from ear tip using an index of 1 to 5 where 1 =• 0.5 cm, 2 = 0.5-1.5 cm, 3 = 1.5-3 cm, 4 = 3-5 cm, and 5 = > 5 cm, and for circumference where 1 = • 2 kernels, 2 = 4 l/4> 3 = 1/4-1/2, 4 = 1/2-3/4, and 5 = 3/4 up to entire circumference of the ear. Materials tested were also evaluated for honey bee toxicity, using an index of 0 to 5 where 0 has no hazard, 1 has short residual hazard, and 5 has long residual hazard.

Sorghum Greenbug Control, 1975

Abstract Plots were arranged in a randomized complete block design with 4 replications in Clay County, Nebraska. Each plot was 2 rows, 30 ft long (30 in centers). Plots were separated by 1 untreated row on each side and 1, 4 ft alley and a 15 ft wide untreated strip at each end. Granular insecticides were applied with a Noble metering device mounted on the planter or bicycle-wheeled carriage. Liquid insecticides were applied with a compressed air plot sprayer mounted on an International Harvester 140 tractor. Relative effectiveness of treatments was evaluated by counting live greenbugs on 10 plants selected at random from each plot until July 21 when 5 plants per plot were examined. Percent control was calculated by Abbott's formula.

Sorghum Greenbug Control, 1976

Abstract Plots were arranged in a randomized complete block design in Clay County, Nebraska. Irrigated plots, summarized in Table 1, were 2 rows, 45 ft long (30 in centers), with 5 replications. Plots were separated by 1 untreated row on each side and a 15 ft grass driveway on each end. Irrigation water was applied with towline sprinklers. All other plots were under dryland conditions and were 2 rows, 30 feet long (30 in centers). Plots were separated by 1 untreated row on each side and 1, 4ft alley and a 15 ft wide untreated strip at each end. Dryland experiments were replicated 4 times except for the recommended insecticide test (Table 2) which was replicated 5 times. Granular insecticides were applied with a Noble metering device mounted on the planter or a bicyclewheeled carriage. Liquid insecticides were applied with a compressed air plot sprayer mounted on an International Harvester 140 tractor. Relative effectiveness of treatments was evaluated by counting live greenbugs on 10 plants selected at random from each plot until July 19 when 5 plants per plot were examined. Percent control was calculated by Abbott's formula.

Two tractor-mounted plot sprayers

Two tractor-mounted plot sprayers

Alfalfa Weevil and Variegated Cutworm Control on Alfalfa in Nebraska, 1975

Abstract Alfalfa weevil control demonstrations were conducted in Franklin and Thayer Counties in south central Nebraska. An infestation of variegated cutworms developed in the Thayer County plot and population counts were made of both pests. Ground-applied plots were 40 by 150 ft and replicated 3 times at each loca-tion. Insecticides were applied with a compressed air plot sprayer mounted on an International Harvester 140 tractor. The air-applied plots in Thayer County were flight-swath wide, approximately 300 ft. long.

Crested Wheatgrass, L. Hesperius Control, 1975

Abstract Treatments were applied to plots located in an established stand of crested wheatgrass. The plots were 12 x 60 feet and arranged in a randomized block design with 5 replications. The test location was on the Joe Goodell farm located in Scotrs Bluff County, Nebraska. Insecticides were broadcast sprayed with a tractor mounted compressed air plot sprayer. Chemicals were mixed with water with a pH of 8.5 and applied at the rate of 5 gallons finished spray per acre. The treatment date was May 26, 1975, at which time the wheatgrass plant bug population was 89.5% adults. The remaining population was 4th and 5th instar nymphs. Pre-treatment and post-treatment plot samples of 25 sweeps per plot were obtained with a standard 12-inch diameter sweep net. Average temperature during rest period was 74.8° F. Wind velocity at application was 3 mph and at sampling varied from 5 to 7 mph. No seed or forage yield data was taken.

A New Plot Sprayer for Pesticide Trials

A New Plot Sprayer for Pesticide Trials

Morphological and Herbicide Susceptibility Differences among Strains of Hoary Cress

Morphological and Herbicide Susceptibility Differences among Strains of Hoary Cress

A Tractor-Mounted Experimental Plot Sprayer

A Tractor-Mounted Experimental Plot Sprayer

A Multiple-Boom Self-Propelled Pneumatic Plot Sprayer

A Multiple-Boom Self-Propelled Pneumatic Plot Sprayer