The dry weather pattern that had settled in over this part of southeastern Texas appears to be broken up by a series of gulf disturbances, with rainfall this past week varying from 5 inches to more than 9 inches.
Grain sorghum and corn harvest should be occurring now, so a little rain would not have hurt us too much. Unfortunately, that was not the case and we are seeing seed sprouting in the sorghum heads and some minor lodging in corn. The balance of cotton is at physiological cutout, so the next hurdle for the cotton will be protecting the bolls from insect damage.
Regarding insects, research has shown that small bollworms will not feed on bolls that are more than 350 heat units (HU) past bloom, stink bugs will not feed on bolls past 450 HU, Lygus 350 HU and for Creontiades we are not 100 percent sure, but our best guess would be it is similar to Lygus.
However, there is a distinct possibility that some fields will experience re-growth and all of the issues that go with restarting the crop are possible. In the case of cotton, where a lesser amount of rain was received and fields are well drained, where 2 or 3 treatments were applied for fleahoppers and where plant growth regulator was used at sufficient rates, the crop still looks good.
With continued rain, boll rot is not only a concern but a real possibility. Most of the crop has been made and bolls are present to the upper tier of the plant.
We are continuing to monitor for bollworms, fall armyworms, stink bugs, spider mites, aphids, Lygus and Creontiades.
Beneficial insect numbers in cotton are moderate to high with lady beetle adults, larvae, big eyed bugs, and tremendous numbers of minute pirate bugs being observed.
Below is an update of recent cotton insect pest observations.
Treatable levels of stink bugs are continuing to be found in numerous fields in the area. The fields that seem to be the most infested are in close proximity or right next to grain sorghum and/or corn fields.
We are beginning to find treatable numbers of Creontiades in many fields in Jackson and Matagorda Counties and I just received a report of some in the Danevang area of Wharton County.
Fall armyworm larvae are continuing to be reported in all of growing areas of Wharton County as well as in the El Maton region of Matagorda County.
Continue to be on the lookout for bollworms. Egg lays are variable across the area with some program fields in many areas having up to 40 percent. Damaged squares and bolls were between 3 percent to 18percent and small worms (up to 15percebnt) as well as medium to large worms (up to 4 percent) are being detected in program fields.
To some degree all cotton fields t we are scouting have worms. On balance the WideStrike and Bollgard II cultivars are doing their job. In a low percentage of the Bt cotton we are scouting we are seeing treatable levels of bollworms and in my opinion to a large degree this “slip” is more of the function of where egg deposition is taking place and subsequent worms are developing rather than a failure of the product.
We seldom see 100 percent control with just about any product that. Simply put, we are seeing that bollworm moths are laying their eggs low in the plant canopy, on blooms, bloom tags and/or bracts with some larvae escaping predation and mortality.