Field Trials of Cockroach Baits, 1989

Field tests determined the relative efficacy and residual life of three consumer cockroach bait stations (Blackflag-0.05% abamectin; Combat-1.65% hydramethylnon; Raid Max-1.0% sulfluramid) and a commercial bait-paste formulation containing 1.37% sulfluramid. The Delaney West Apartments, a multi-family housing complex located in Gary, Indiana, served as the test site; individual apartments served as the replicated experimental unit. Bait stations (12) were positioned as recommended by the manufacturers. Seven stations throughout the kitchen; cabinets under the kitchen sink (3 stations), cabinets above the sink (2), and on the floor near the stove (1) and refrigerator (1). Three stations were positioned “optional sites” near active infestation sites: e.g., garbage collection, closets, kitchen furniture, etc. Two stations were placed in the bathroom, behind the toilet and beneath the sink. Stations were oriented horizontally (where possible) and attached to surfaces with sticky fasteners. Bait-paste applications mimicked bait station placements; ca. 40, 0.5-g placements were located throughout the kitchen and bathroom area. Population levels were estimated by visual counts throughout kitchen and bathroom areas, and a minimum pretreatment count of 20 cockroaches was required for any apartment to be considered as a test. Each treatment was replicated in 12-15 apartments, but sample size after treatment varied due to apartment vacancy or lack of cooperation. To determine efficacy, counts after treatment were reduced to percent reductions from the pretreatment counts. The data were transformed by signed-ranks prior to analysis with ANOVA models, followed by LSD (P = 0.05) to determine significance among the treatments at each posttreatment census.