Tom Smith, local consultant, reported that “a number of early planted [cotton] fields [are done] until defoliation, and a number of later planted fields may need 1 or 2 sucking-bug sprays and bollworm protection. We treated a few fields last week for target spot and mildew. I have observed some unusual piercing-sucking species in cotton over last couple/few years.”
I preliminarily identified them as the spot-sided coreid and the helmeted squash bug, but I could be incorrect.
Drake Perrow, crop consultant in Cameron reported that “where pyrethroids went out last week, many fields are having to be retreated with the big guns [more expensive insecticides for bollworm] this week.”
Fleming McMaster, local crop consultant, called with a report of many velvetbean caterpillars (VBC) in soybeans. I can confirm that we have good pressure from VBC right now in soybeans in the southern portion of the state.
Cotton Situation
We are in a holding pattern with high trap captures of bollworm in pheromone traps and stink bugs really standing out in the crop. Any late-planted, 2-gene Bt cotton should be watched for bollworm.
Bollworm captures were high but trending downward on the last check, so we might be on the decline next week. Just look after the late-planted cotton to make sure nothing is getting through.
Pressure from stink bugs has picked up here towards the end of “stink bug month” around here, and they are easy to spot on bolls. Keep using the dynamic boll-injury threshold for stink bugs to finish the season. Most fields are probably in the fifth to seventh week of bloom.
Soybean Insects
Defoliation has really picked up this week, with velvetbean caterpillar (VBC) joining forces with soybean looper (SBL) to seriously chow down on foliage in the crop.
Things can happen quickly with VBC. My crew and I collected hundreds of very large VBC this morning with ease, and I sprayed an efficacy trial for VBC to see what products will clean them up this season. I will report back next week on that.
In 2019 we dealt with troublesome populations of this migratory species in spots where they were very tough to control with many insecticides. Hopefully, VBC are easy to take out this year. I should know on Monday. Continue watching this complex of defoliating caterpillars, and don’t let defoliation exceed 15% once pods are filling.
Use a sweep net or a drop cloth to make counts of insects to see what species you have because insecticide choices depends on proper identification of species. Any late-planted soybeans that are just now blooming should be checked for podworm (same as bollworm), for sure, as numbers moths in pheromone traps were high again this week.
Also, stink bugs are our number one soybean insect pest group, and they have exploded. Check closely for stink bugs and treat if you have more than 1 per row-foot (based on 38-inchrow spacing) or 1 to 2 per 10 sweeps.
Redbanded stink bugs are in the mix again this season, and they can be tougher to control.
