LABORATORY EVALUATION OF DESICCANTS AND INSECTICIDAL SOAP APPLIED TO VARIOUS SUBSTRATES TO CONTROL THE DEER TICK IXODES-SCAPULARIS

Desiccant and soap pest control products were tested against Ixodes sc apularis nymphs on sod, pachysandra, landscaping stones and pinebark w oodchips in a laboratory study. High mortality (91-100%) was obtained with the silica-based desiccant Drione and Safer's insecticidal soap ( SIS) treatments except for SIS treated woodchips. SIS and Drione conta in 0.2 and 1% pyrethrins, respectively. SIS may be absorbed by the woo dchips and not picked up by the nymphs as mortality decreased to 78%. Diatomaceous earth and Dri-die reduced nymphs by only 10-41%; neither desiccant contains insecticides. Nymphal mortality increased 15-17% af ter 20 or 100 ml of water was sprayed over sod plugs treated with SIS or Drione. The addition of isopropyl alcohol (ROH) to SIS increased th e efficacy of SIS against nymphal I.scapularis on treated sod plugs bu t not on treated landscaping substrates. Drione, SIS, SIS-ROH and chlo rpyrifos 50WP treated landscaping stones and pinebark woodchips result ed in 88-95% and 72-96% nymphal mortality, respectively. Unexpectedly, these substrates and treatments affected tick movement as well. Effec tive pest control products applied to xeric landscaping substrates pre sent in maintained beds and borders near wooded areas could deter tick movement and provide significant levels of tick control.