Comparing an IPM pilot program to a traditional cover spray program in commercial landscapes.

An integrated pest management (IPM) pilot program for landscape plants was implemented during 1997 and 1998 on two commercial, two residential, and one institutional property managed by landscape professionals. When compared with preprogram, calendar-based cover spray program costs at these sites in 1996, the IPM program was cost-effective at one of the five sites in both 1997 and 1998, and cost effective at a second additional site in 1998 when the cooperator, initially skeptical of IPM, discontinued calendar-based cover sprays performed in 1996 and 1997. The mean cost per site was $703.40 (preprogram), $788.26, and $582.22 in 1996, 1997, and 1998, respectively. Volume of pesticide applied decreased a mean of 86.3% on the four sites not receiving cover sprays and increased 2.3% at site 2 (still using cover sprays) in 1997. In 1998, pesticide volume was reduced an average of 85.3% at all five sites compared with preprogram levels. The majority of insect pest problems were corrected using spot sprays of insecticidal soap or horticultural oil or by physical means such as pruning. One-third of the woody plant material on the commercial and institutional sites consisted of holly, juniper, and azalea. The most prevalent pests encountered were mites (Tetranychidae), aphids, lace bugs, scales, whiteflies, and Japanese beetle. Spiders were the most abundant group of predatory arthropod and ants, green lacewings, and lady beetles were also well represented in the managed landscapes.