This is the time of year that squash vines may be looking great. However, beware of the squash vine borer. The runners or entire plant will suddenly wilt due to the presence of squash vine borer larvae in stems and leaf stalks. Masses of coarse, yellow-green excrement or frass are pushed from the holes in the base of stalks. The moths (adult stage) may be seen flying around the base of the plants during the day and are wasp-like with metallic copper-green forewings, and an orange and black abdomen.
Treating the base of the plants with either malathion or rotenone works to control borers before they enter the stems not after the fact. It s possible to remove borers by splitting the infested stems with a knife and then covering the slits with moist soil. In fall, destroy the vines immediately after harvest and cultivate the soil to destroy overwintering pupae.
This article originally appeared in the 7/18/2003 issue.
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