Sticky wing pheromone traps are very useful for detecting moth activity at a low cost. Typically, the moth counts in traps provides a forecast for caterpillar activity in crops in the coming days (caterpillars must be confirmed by direct counts in the crop). Based on sticky wing pheromone counts from 14 locations across Alabama (mix of commercial farms and research stations with peanuts and/or horticultural crops), we have some clear trends on increasing moth activity that are summarized here.
Over the past 15 days, we have collected 13 tobacco budworm (TBW) moths, 8 corn earworm (CEW), 92 beet armyworm (BAW), 14 fall armyworm (FAW), 25 cabbage looper (CL), 3 soybean looper (SL), 416 lesser cornstalk borer (LCB), and 55 squash vine borer (SVB) moths from various locations. Clearly, there is lot more beet armyworm activity compared to the fall armyworm that typically migrate late to row crops like peanuts. We have noticed high cabbage looper caterpillar feeding in vegetable crops that corresponds to the high moth numbers seen in sticky wing traps.
LCB is a very good indicator species for drought and stress conditions – the very high moth numbers is a sign of increased risk to crops like peanuts later in the season. LCB is a hidden threat in peanuts and can cause high crop damage to late-stage peanuts; irrigation for improving soil moisture significantly reduces the threat.
Squash vine borers have limited host plant range and can reduce yields as caterpillars bore into the stem. The vine borer moth is a red moth that behaves like a wasp trying to lay eggs at plant bases. Vine borer activity is favored by the drought conditions experienced over the past several weeks. Even with one or two generations of these moths, the damage to commercial crops or garden crops can be significant, so stay alert and keep reading IPM pest alerts through the summer.
While looking for caterpillar and other insect pests, don’t forget to take into account the beneficial insect populations that are critical for small insect control such as aphids, whiteflies, thrips, and spider mites that often take on pest status this time of year. Rampant use of organic or conventional insecticides only aggravates pest species. For detailed insect pest management information, refer to the SE Vegetable Production Guide or the Peanut IPM Guide after confirming infestation.
Contact a Regional Extension Agent for assistance with crop scouting and pest identification services.