Use of visual traps for monitoring insect pests in the Massachusetts apple IPM program

Abstract

Visual traps were evaluated for effectiveness as monitoring devices for the tarnished plant bug ( Lygus lineolaris, TPB), European apple sawfly ( Hoplocampa testudinea, EAS) and apple blotch leafminer ( Phyllonorycter crataegella, ABLM). Results indicate: 1. A significant positive linear relationship between on-tree fruit injury surveys and cumulative captures on white, sticky-coated rectangles of TPB adults, for the tree development periods silver tip through tight cluster or silver tip through late pink, and for captures of EAS adults in blocks receiving no pre-bloom insecticide sprays. 2. A significant positive relationship with linear and quadratic components between on-tree fruit injury surveys and cumulative captures on white rectangles of EAS adults in blocks that did receive pre-bloom insecticide sprays. 3. A significant positive relationship with linear and quadratic components between peak mines per leaf and cumulative captures of ABLM adults on tent-shaped, red enamel (sticky side up) traps for silver tip through late pink or silver tip through two weeks past petal fall. Provisional economic injury levels are suggested as 2.0% and 0.7% fruit injury and 0.13% mines per leaf for TPB, EAS and first generation ABLM, respectively. Provisional action threshold levels based on these economic injury levels are presented for TPB (cumulative capture of 2.4 per trap for silver tip through tight cluster or 4.2 per trap for silver tip through late pink respectively), EAS (cumulative capture of 4.7 per trap in blocks that received no pre-bloom insecticides, or 5.5 per trap in blocks receiving pre-bloom insecticides) and ABLM (cumulative capture of 13 moths per trap from silver tip through late pink).