CURRENT CROP CONDITIONS
The area cotton crop is continuing on schedule with program fields ranging from full bloom to less than three nodes above uppermost first position blooms. Many of the area program fields are still being irrigated at this time. Many of you have asked when you should quit irrigating, and the answer is not that easy. We do know that the water demand for cotton will decrease after bloom. And I do know that if you shut down your wells now, you will shed more fruit than our heaviest beet armyworm infestation can eat. For the most part, when the bolls are filled on the positions that will make a good harvestable boll, we can turn the water off. For some of you, that will be towards the end of August and for others, that will be mid September.
The COTMAN computer model is projecting that most fields will be safe from bollworm feeding starting the last week in August through the first week in September. For defoliation, the model is saying September 4 on our fields that cutout way too early to September 24 on fields that cutout this week. These projections change weekly due to temperature fluctuations over and under the long term average.

WHAT THE SCOUTS ARE FINDING
Nothing much has changed since last week, with beet armyworms, aphids and bollworms dominating the picture. Every program field that we have checked this week has populations of aphids and beet armyworms. Cotton aphids are ranging from infestations located in the terminal and on squares of the plant to over 50 per leaf. Beneficial insects

are still hit and miss in most of our fields. We have seen economic infestations being completely cleaned up by beneficial insects. Based on my observations, aphid infestations have to be widespread within the field and over 75 per leaf in order to attract enough beneficials to decrease these populations in a timely manner. Most of the fields with economic infestations are being treated with Intruder. We have used this product at 0.6 ounces per acre with excellent results. The 0.6 ounce rate of this product is comparable in price to Furadan but without the hassle of extended re-entry intervals.

Bollworm eggs are still being found in most program fields and are ranging from zero to 15,000 per acre. Larvae are ranging from 0 to 10,000 per acre. In fields that have reached cutout and have shed all the small fruit at the top of the plant, the infestations that are ranging from 5000 to 10,000 small worms are decreasing down to less than 3,000 worms per acre within 5 days. However, in heavily irrigated fields that are stuck at four nodes above upper most first position white bloom, these infestations are doing quite well. Most of the eggs being found are hidden in the lower to middle portion of the canopy making detection difficult at best. I have yet to find any infestations over 20,000 per acre in any of our program fields, although I have heard reports of infestations over 30,000 per acre in the Southern portion of the County. I am still using a threshold of 8,000 to 10,000 worms per acre in the lush cotton, call me scared if you want to, I just think that there are too many small third position bolls and fourth position squares to provide food for these newly hatched larvae. In fields that have cutout early due to stress, I have raised the threshold to 10,000 to 20,000 worms per acre and I do not think twice about walking away and leaving 10,000 to 15,000 small worms per acre.

Beet armyworms are now being found in every program field. Most of these infestations at this time are light and are concentrated to very small portions of the field. With that said, as the days click by we are finding more and more hot spots of this pest. Infestations are ranging from less than 1,000 per acre to well over 45,000 per acre. The only two products that have been used in our program fields are Intrepid at 6 ounces per acre and Steward at 10 ounces per acre. Both of these products have performed quite well through both ground and aerial applications. I would like to make quick mention of the common but incorrect scouting technique used for this pest. Do not go hike your fields for 15 minutes in search of an obviously damaged plant and drop to your knees and start counting worms. You will greatly overestimate your overall worm count. While I am at it, do not wait five or six days to make up your mind weather or not to treat for this pest and then try to successfully control large larvae. I consider everything over ½" in size a large worm.

Suggested insecticides for beet armyworm control

Suggested Insecticides for control of aphids in cotton.

Suggested Insecticides for control of bollworms.

* The synthetic pyrethroid insectidides recommended for control of bollworms also will control boll weevil. However, application intervals similar to those recommended for the traditional phosphate insecticides (3 to 5 days under heavy pressure) are necessary to provide adequate control. When treatments are to be made for a bollworm-boll weevil complex a suggested treatment regime is to use a pyrethroid followed 3 to 5 days later by a phosphate or carbamate boll weevil insecticide.

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