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This Southern Blacklands Pest Management Newsletter and other newletters and information can be obtained from the Williamson County Extension Service Web Site at williamson-tx.tamu.edu. Also, this newsletter as well as other Extension IPM newsletters from across the state can be viewed at the Texas Pest Management Association website at www.tpma.org.

GENERAL SITUATION

Scattered showers fell across the Southern Blacklands on July 1 and 2. The showers deposited between 1.25 to over 6 inches of rain. The heaviest rainfall totals occurred in Milam County between Thorndale and Cameron.

CORN AND SORGHUM SOIL INSECT PESTS

The majority of the grain sorghum has passed bloom stage and thus susceptibility to sorghum midge. Sorghum midge levels range from 10 to 24 per 100 heads checked. Numbers are heaviest around the margins of fields, where they often reach 3-5 per head. However, midge numbers drop off quickly as you move into the field.

Stinkbugs and headworm numbers for the most part remain low. However, we are seeing higher levels of these pests in fields that have recently been treated for grasshoppers. Stink bugs are ranging from 4 to 32 per 100 heads checked. Headworms numbers are ranging 2 to 22 per 100 heads checked.

COTTON

Cotton ranges from pinhead square stage through four weeks into bloom. Much of the cotton has put on a good fruit load. However, there are some fields that are having difficulty fruiting up. These fields need to be monitored carefully for fleahoppers, square set and need of a plant growth regulator.

Aphid levels are nearly nonexistent in most fields. Unfortunately, a few of the real late fields still have aphids, but beneficials are working to clean them up.

Fleahoppers continue to cause problems in some fields. The fields in reference have some plants that are loaded up well and then have plants that cannot seem to set a square. Fleahopper pressure in these fields is not as high as it was earlier in the season, but nevertheless, is heavy enough to still cause loss of tiny squares. Because of the expected increase in moth egg lay, we are trying to stay out of the fields, maintain as many beneficials as possible, and let the fields try to set on their own. However, this has not worked as well as we had hoped.

Boll Weevil activity has picked up slightly over the past week. Puncture square counts range from 0 to 8 per 100 squares checked, with most fields averaging 0-2. Most fields still have very few signs if any of weevil activity. However, it is expected that first generation adults will begin emerging. At that point, more punctures will likely be found.

Bollworm/budworm levels have begun to increase through the first few days of July. Number of eggs and larvae range from 0 to 10 per 100 plants checked. Most fields are averaging 4-6 eggs and 2-4 larvae per 100 plants checked.

The much welcomed rainfall has cooled down soil temperatures and therefore may cause a slight delay in adult moth emergence from the soil. In addition, budworm trap catches have began to increase. This will be important information to stay on top of, especially as we run into heavier worm populations that require an insecticide application.

We still have a long way to go with this cotton crop and a lot of potential obstacles to overcome. When economic thresholds are reached for worms, try to stay away from using pyrethroids as long as possible. It is important that we avoid contributing to a resistant budworm population as long as possible, and this can be accomplished by avoiding unnecessary pyrethroid applications.

Refer back to Vol. XXI No. 7 of Southern Blacklands Pest Management News for more information on scouting and economic thresholds for bollworm/budworms.

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