“The majority of our cotton is in stinkbug territory – third to fifth week of bloom when we have heightened boll susceptibility. Check bolls for internal injury and follow the dynamic threshold, which should be familiar to everybody now. This is when we have the most bolls that could be injured, so we have the greatest risk to yield impacts from stinkbugs.
“When making a treatment decision, consider which pests are a problem and whether you can make one treatment that will control more than one of them. We have options that control stinkbugs and might have some effect on spider mites.
“In our area, a pyrethroid can still control escaped bollworm and could be used in fields with low worm populations. If bollworms are at threshold, we might need to make a different treatment decision. What you chose depends on whether the treatment is focused on stinkbugs or bollworm.
“For 9 out of 10 of our fields, the priority likely is stinkbugs. Stinkbugs are the No. 1 pest of cotton in South Carolina and much of the Southeast. But, scout closely where you have a history of bollworm problems.
“Spider mites are becoming more noticeable. Aphids are gone, but we have scattered signs of cotton leafroll dwarf virus. We can’t do anything to control it – and likely don’t need to do anything. We are still learning about this virus. With scattered and light symptoms, we aren’t likely to see broad yield reductions.
“In soybeans, I checked a field today (7/28/20) that is at R3 and it’s loaded with bugs and caterpillars – kudzu bugs, stinkbugs, podworm, soybean looper, velvet bean caterpillar and green clover worm. Defoliation is starting to increase quickly. So, we know insects are in the system. Scout closely to determine where they are a problem. Tailor your treatments to the populations you find. We don’t need to treat every acre the same.”
Sally Taylor, Virginia Tech Extension Entomologist, Tidewater REC
“Hopefully, everyone is receiving the rain that they need. Spider mites are still a concern and we should avoid flaring them. Remember that mites can be present and not cause losses. We can avoid needing miticides by being conservative with insecticides. Plant bugs are spotty across the region, between neighboring fields, and even within fields. Base spray decisions on what you find in your fields.
“My program is available to help if you have scouting questions and concerns. Do not hesitate to reach out to us.
“Our bollworm flight is picking up this week and we likely will see our trap catches increase over this week and next. Preventive sprays in two-gene cotton are recommended when 25% of terminals and/or leaves next to blooms have eggs. The highest percentage my team has found this week is 3%.
“Be conservative when planning sprays. Growers have several options for worm control in cotton, peanuts and soybeans. Consider whether you have eggs or worms when you decide which product to use. If you are unsure which product performs best in your field situation, or need to confirm which products offer residual control, contact me, your local ANR agent, crop consultant, or chemical sales provider.
“Cotton leafroll dwarf virus (CLRDV) has been detected in Virginia. Please reach out to us at the Tidewater station if you observe unusual plant growth not explained by herbicide injury or drought stress and/or you found aphids in your field. You cannot control the virus by spraying aphids.
“Also, I don’t think there is any reason to be concerned over yield loss until we know more about the virus and what causes its symptoms.”
Ron Smith, Extension Entomologist, Auburn University
“Overall, insects are quiet in Alabama. We are finding low levels of aphids in many fields, and a few tarnished and clouded plant bugs are present in nearly every field. But we haven’t seen any at treatable levels recently. Spider mites are in a number of fields, and the longer we stay dry, the worse mites will get.
“Stinkbug pressure varies from field to field, but they are quietly building. Two issues influence stinkbug populations: proximity to corn or peanuts and the size of the field. Populations will be higher close to corn or peanut fields. They move out of corn when it dries down. Although stinkbugs don’t harm peanuts, they move to cotton from peanuts all season long.
“Field size influences populations because stinkbugs don’t fly well. So in fields that are 75 acres or larger, it takes a long time for them to hit threshold. Ideally, we could make border sprays. However, that approach isn’t practical for many growers who have large fields spread across a wide area.
“We haven’t had any bollworm calls on 2-gene cotton. If we look long enough, we can find an escaped worm. However, they’re at a very low level and in both central and south Alabama we are already past the moth flight out of corn. Since we are past the flight and we still don’t have many escaped worms, it looks like it’s going to be a light bollworm year.
“The pest we are most concerned about going forward is the silverleaf whitefly. We don’t think we have any fields infested yet, but we are checking likely areas again on Thursday (7/30).
“Where we have moisture, cotton is adding a lot of fruit. We really would like to have a rain over most of the state this week.”
Dominic Reisig, NCSU Extension Specialist, Entomology, Plymouth, North Carolina
“Some places received recent rains, but we still have dry spots. Some of this corn looks absolutely burned up. We’re supposed to get a soaker for the next few days, so we’ll be happy to see that.
“We are spraying some fields for bollworms. We don’t see widespread issues, but we definitely have early pockets. The moth flight is steady, and we haven’t seen it tick down yet.
“Most of the questions involve taking out plant bugs and stinkbugs without flaring those things that have been nagging us all season, such as spider mites and aphids. The primary question is: ‘Should I add an insecticide to the tank when I’m making a trip across the field?’ The answer is, ‘It depends.’
“Fortunately, stinkbugs have been light all season across crops, and folks are talking about how light they are in cotton. Growers in northeast North Carolina aren’t getting a break from plant bugs. It’s too early to call it a heavy year, but we sprayed more than usual in the central Coastal Plain. Outside of that area, we only see scattered plant bugs populations.
“We expect worm calls from soybean farmers to start next week, and more sprays are going out.”
Phillip Roberts, Extension Entomologist, Tifton, Georgia
“Scattered pop-up thunderstorms have been developing, and we desperately needed rain on our dryland cotton. Some fields received it, others haven’t yet. On dryland acres that haven’t gotten a rain, the cotton is suffering, and it’s been a while since a good, gentle rain fell across a wide area.
“Overall, four pests are on everybody’s mind – whiteflies, spider mites, bollworms and stinkbugs.