TRAPS FOR MONITORING PEAR THRIPS (THYSANOPTERA, THRIPIDAE) IN MAPLE STANDS AND APPLE ORCHARDS

The effect of trap color and orientation on capture of adult pear thrips, Taenioththrips inconsequens (Uzel), was tested in Connecticut and Massachusetts. In single degree-of-freedom comparisons, vertically positioned fluorescent yellow rectangles caught the greatest numbers of thrips compared with all other vertically positioned hues tested, but numbers captured on fluorescent yellow did not differ significantly from captures on commercially available yellow, dark red, or white traps. Dark green and dark blue traps were least attractive to adults. In season-long trials of commercially available yellow, red, and white traps alone in apple and maple, yellow traps captured the most thrips. Fluorescent yellow traps in horizontal adhesive-down and 45-degrees-adhesive-down orientations caught significantly fewer adult thrips than cylindrical, vertical, horizontal adhesive-up or 45-degrees-adhesive-up orientations of the same hue. Upward-facing 45-degrees orientations caught significantly more thrips than vertical rectangles of the same hue. Captures on vertical rectangles and on vertical cylinders did not differ significantly. We found that the most practical visual trap to estimate relative density and activity of pear thrips was a commercially available, nonbaited vertical yellow rectangle (16 by 19.5 cm).