A vacuum apparatus was used in a test bench environment to determine the effects of two operational parameters on vacuuming efficacy for an insect pest. Nymphs and adults of tarnished plant bug, Lygus lineolaris P. de. B. (Hemiptera: Miridae), marked with fluorescent powder, were positioned on strawberry plants according to three height classes. Three speeds of inlet passage (i.e., 2, 4 and 6 km h−1) and two heights (passage at 2/3 and 3/3 of the canopy) of inlet relative to the top canopy of the plants were investigated. After vacuuming the marked insects remaining on the plants were then found using a UV light and the class height of their position on the plant and the substrate (i.e., soil, leaf, stem or fruit/flower) were noted. The efficacy of the vacuum was optimal when the inlet was passed at 4 km h−1 with the inlet at a height of 2/3 of the strawberry canopy. Nymphs were usually vacuumed more efficiently than adults. Most (64.5%) individuals that were not vacuumed did not change position after inlet passage. Most (85.9%) individuals that changed position after inlet passage experienced vertical, mostly downward, movements.

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An experimental plot sprayer, with a new mixing chamber and water measuring system, was developed to minimize operator exposure to pesticides during mixing and rinsing. Premeasured herbicide samples in 50-ml capped test tubes are emptied into the mixing chamber, and water is measured, rinses the test tube, and drains into the chamber to produce the spraying volume. This system eliminates operator contact with the chemicals and can be flushed quickly between plots to eliminate contamination. Rinsing efficiency with atrazine was greater for a suspension than a wettable powder formulation but less than 0.1% of the initial concentration was detected in water following the first or second rinsing.