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Onions were planted as transplants 15 Mar in a field with furrow irrigation west of Platteville, CO (Weld Co.). Plots were 8 x 15 ft in a complete randomized block design with 4 replications. Treatments were applied with a CO2 hand sprayer delivering 48 gal/acre (24 gal/acre in treatments with 1/2 volume) at 30 psi. Applications were made 3 Jul (Expt. 1) and 27 Jul (Expt. 2). Evaluations were made by counting the number of nymphs and adults on 15 plants in each plot. These counts were made 1 day prespray; 3 and 8 days postspray (Expt 1) and 3 days postspray (Expt 2). Percent control was determined using adjusted mortality.

Onions, cv Brown Beauty, were seeded 2-3 Apr in a field under furrow irrigation at the Colorado State Univ Bay Farm in Fort Collins, Colorado (Larimer Co.). Plots were 8 × 30 ft and treatments were arranged in a randomized complete block design with 4 replications. Treatments were applied with a CO2 hand sprayer delivering 48 gal/acre at 30 psi or were broadcast (Diazinon). Initial application of all insecticides in the test was made 31 Jul (Trial #1). Additional applications, made if mean number of thrips exceeded 10 per plant over all 4 replications in prespray counts, were 20 Aug (Trial #2) and 28 Aug (Trial #3). Evaluations, made by counting the number of nymphs and adults on 10 plants in each plot, were: Trial #1-31 Jul (prespray), 2 Aug (2 day), and 7 Aug (7 day); Trial #2-16 Aug (prespray), 23 Aug (2 day); Trial #3-23 Aug (prespray), 30 Aug (2 day). Percent control was adjusted based on prespray counts in both treatment and control plots. There was no insecticide application prior to the test.

Onions were seeded 19 Mar in a field under furrow irrigation at the Northern Colorado Research and Development Center in Greeley, Colorado (Weld Co.). Plots were 8 x 30 ft and treatments were arranged in a complete randomized block design with 4 replications. Treatments were applied with a CO2 hand sprayer delivering 48 gal/acre (24 gal/acre in treatments with 1/2 volume) at 30 psi on 21 Aug. Evaluations were made by counting the number of nymphs and adults on 15 plants (2 days postspray) and 10 plants (9 days postspray) in each plot. There were no insecticide applications prior to the test. Pest infestation Was low (adults) to moderate (nymphs) at time of testing.

Plots were established in a grower’s field west of Ft Collins where an outbreak of alfalfa webworms was occurring. Individual plots were 8 by 15 ft arranged in a randomized complete block with 4 replications. Applications were made 10 Jul using a CO2 boom sprayer delivering 48 gal/acre at 25 psi. First sampling was 13 Jul taking 12 sweep-net samples/plot. A second sampling 18 Jul involved 10 sweep-net samples/plot.

Woody ornamentals were tested for sensitivity to insecticides, miticides and surfactants used for ornamental/shade tree pest control. Testing included seedling nursery stock, 3 mo to 1.5 yr old, and shrubs at the Colorado State Forest Service nursery; shrubs at the Plant Environmental Research Center; and trees on the Colorado State Univ campus. Seedling nursery stock received either 1 application (3 Sep), or 2 applications (3 Sep and 10 Sep). Mature trees and shrubs received 2 applications (12 Sep and 18 Sep). Concentrations of pesticides used were 4X label rates and were applied until point of run-off. Plants were evaluated 7 and 14 days after last application.

‘Late Flat Dutch’ cabbage was transplanted at 2-ft spacings (22-inches between row) at the C.S.U. Bay Farm on 1 Jun ’84. Plot size was 4 plants by 2 plants, separated by borders and arranged in a randomized complete block design with 4 replications. Treatments were applied 7 Aug using a CO2 compressed air sprayer delivering 90 gal/acre. Plots were evaluated 10 Aug and 27 Aug. Cabbageworm larvae and false chinch bugs were counted as totals from the center 4 heads in each plot. Aphids, primarily the turnip aphid, Hyadaphis erysimi (Kaltenbach), were counted from 2 leaves selected from each center head.