Across the state:
- Jonathan Croft, county agent in Orangeburg County, reported that he is seeing a few aphids in older cotton.
- Charles Davis, county agent in Calhoun County, had the same report as Jonathan…just aphids.
- Drake Perrow, consultant and producer in Calhoun County, reported that he is seeing large hatch outs of immature grasshoppers and building aphids on some herbicide-stressed cotton at pinhead square.
- Hannah Mikell, county agent in Clarendon County, reported seeing aphids and a lot of false chinch bugs.
Current Lineup: Cotton Insects
Aphids and tarnished plant bugs (TPB) are building in cotton, especially early-planted fields. In some 12-node cotton, I easily found TPB and cotton aphid this week. We are also seeing many winged aphids in later-planted cotton (4-5 leaves), so aphids will be something to watch out for in the next couple of weeks.
Do not go spray for aphids just because they are there. We need a very good reason to spray for aphids. Plenty of data indicates that we do not gain yield from aphid sprays – well, almost never.
Just watch them, and pay attention to the other stressors on the crop. If it gets to be too much, we can take out aphids if the natural fungus, Neozygites fresenii, doesn’t show up or is late in taking out aphids.
Know Your Bugs
Properly identifying tarnished plant bug adults and obtaining square retention counts should be the focus right now. Make sure you can identify adults of TPB.
Adults of TPB have a tarnished appearance and a small, pale “letter V” on the dorsum (back or top side). Don’t mistake false chinch bugs for TPB. False chinch bugs (FCB) are dark gray with lighter wings. Also, they are much “thinner” than TPB and do not have the “tarnished” appearance.
Bigeyed bugs (BEB) are predators (beneficial) and are similar in size to TPB and FCB, but they have large eyes that protrude on the sides of the head.
Know how to recognize these adults. Adults of TPB will be a little larger than FCB and BEB. Adults of FCB will be quick and in groups most likely. Adults of TPB and BEB will be solitary in most cases. Don’t confuse the species.
AgFax Weed Solutions
Tarnished plant bug is more important than false chinch bug, as TPB can feed directly on squares and cause fruit loss. FCB can be very numerous and almost swarm on cotton plants, but they cause far less injury and only need to be controlled at very high levels on stressed plants.
Bigeyed bugs are good guys. Do not count them in plant bug counts. Remember, monitor square retention and sweep for plant bugs. You must be able to properly identify the insects in the field.
Hopefully, we can have in-person scouting workshops next month. Stay tuned.
Continue to monitor for aphids and spider mites, too.