By Clint Thompson
The Georgia Cotton Commission (GCC) and Phillip Roberts, University of Georgia Cooperative Extension cotton entomologist, caution growers about what insect pests are currently impacting this year’s crop.
Those insects include cotton aphids, plant bugs and stink bugs.
Roberts emphasizes aphids will infest 100% of cotton plants throughout Georgia. He also stresses that during his research career, he has rarely seen a yield response when spraying for aphids. Most producers do not manage aphids with insecticides but wait on a naturally occurring fungus which will crash populations.
The fungus starts during late June or early July and moves north and east. If growers observe gray fuzzy aphid cadavers, it indicates the fungus, and populations will crash in less than a week.
Growers must be mindful that high aphid populations on late-planted cotton could stress seedlings and delay maturity a few weeks. Growers might want to be aggressive with aphid management on late-planted cotton.
Tarnished plant bugs are being observed in some parts of Georgia. Management options are being made on scouting and the use of thresholds. Adult plant bugs are migrating from weedy hosts, and squaring cotton can be an attractive host plant. Later planted cotton may avoid the initial migration to cotton but will remain susceptible to plant bugs later in the season.
Stink bugs do not pose a threat to cotton until it begins setting bolls. Later planted cotton is at a greater risk to stink bugs compared to early planted cotton. Roberts stresses that growers trust their scouting and thresholds. Make sound decisions on what pests are present and be timely with insecticides.