The next two weeks should be key weeks if indeed we are going to see caterpillars in the peanut crop; so keep your eyes open. The last week or so has been good to many of you with some much needed rains. This really helps with the spider mites. In fact, when we get two consecutive days of cloudy weather and temperatures below 90 F, that really helps a fungus that attacks mites and knocks populations back. However, mites still need to be watched carefully given the hot summer and the forecast for the next week. As we move further along into August you can feel more confident applying a compound like Brigade or Danitol for mites and caterpillars with less concern about a rebound of the mite population. Comite is an effective mite product but can be hard to find in certain areas. The later we get in the season, the more practical it is to spray once for mites and then take a wait and see approach and hope you get favorable weather.

Caterpillar sprays should be considered only if thresholds are met. In fields with normal or better leaf canopies, treat if caterpillar populations reach 4 per row foot; and this increases to 6 per row foot towards the end of August. Many peanut fields are treated when populations are well below threshold, a practice that does not reap any benefit, and could increase the risk of other problems. If plants have poor canopy growth, you may be justified in using a lower threshold, but again, it is important to at least try to determine the number per row foot and abide by the thresholds. Another consideration is what species of caterpillars are present. They all count equally in the threshold, but if fall armyworms are in the mix, a non-pyrethroid may be needed to achieve good control.