Trap catch of western flower thrips (Thysanoptera : Thripidae) as affected by color and height of sticky traps in mature greenhouse cucumber crops

Catch of western flower thrips, Frankliniella occidentalis (Pergande), on sticky traps was assessed by height, color, and sex in commercial greenhouse cucumber crops grown on 2.1-m-high trellises. The catch of both sexes was greatest at 2.4 m above the floor, less at 1.8 and 3.0 m, and least at 1.2 and 0.6 m. Catches at 0.6 and 1.2 m did not differ significantly among colors. At 2.4 m, catches on blue, violet, yellow, and white traps were traps were not significantly different, but were significantly greater than catches on green, UV + white, and black traps. At this height, blue captured more females than other colors, and yellow captured more males. Results were similar in a trial with commercial yellow sticky traps, except that the catch of females was greatest at 3.0 m.