This week I was under the weather a bit, but in the scouting I did get to I saw cotton fleahoppers in lower numbers. This was didn't surprise me since most of the places I check with squaring cotton have been treated for fleahoppers sometime in the last two weeks. I did see one more verde plant bug in Jackson county this week as well. The threshold for verde plant bugs is 20-25 insects per 100 plants with using a beat bucket. Verdes can feed on fruit up to bolls about an inch in diameter.
|Nymph (A) and adult (B) of Verde plant bug, Creontiades signatus Distant (Hemiptera: Miridae), which causes lint and seed staining and deterioration, seen in green (C) and open (D) cotton bolls. https://ccag.tamu.edu/entomology/|
Fleahoppers feeds on plant materials, and will feed on cotton squares. Keep a sharp eye out for this insect, the adults are very flighty and are often easily scattered when walking fields. I try not to let my shadow hit a plant before I get close enough to look at it so I can see the adults before they fly. Below I have two photos, one of the nymph and one of the adult insect. The nymphs of these insects are also quite small, about the size of an aphid. They are also a pale green color, but lack wings. They lack cornicles (tailpipes) that an aphid would have, and tend to be more mobile than an aphid. Fleahopper nymphs also lack the bands on the antennae a few other species of plant bugs have, and have a similar body shape to the adult bug.
|Cotton Fleahopper Nymph|
|Cotton Fleahopper Adult|
Fleahopper feeding will cause squares to drop. Plants can recover for and compensate for some square loss, but the threshold for fleahoppers is 15-25 per 100 plants. I check for fleahoppers by inspecting the plant terminals once they start squaring. I look at 25 plants per stop in the field, usually checking 100 plants total in an 80-100 acre field, more if the field is larger.
I am currently looking for sugarcane aphids in sorghum fields as well. I've found them with little difficulty in johnson grass, but have not located them in field in Jackson or Matagorda counties yet. If you have some, please let me know and I can confirm their presence in the county for our sugarcane aphid mapping project.
If you're not sure what kind of insect you have, feel free to drop it by the Wharton county office.
Looking for more information? Check out the Cotton Insect Guide
Need help with weed control? Check out the Weed Management Guide