CURRENT CROP CONDITIONS
The area cotton crop is continuing on schedule with program fields ranging from 7 nodes above uppermost white bloom to two nodes. If the current weather conditions remain the same, all program fields will have acquired enough heat units to be safe from weevils and worms by August 23 with the earliest fields acquiring enough heat units by August 8. Currently we are receiving an average of 24 heat units per day. All program fields will be ready for harvest aid applications by September 15 with the earliest fields being ready by August the 28.

WHAT THE SCOUTS ARE FINDING
Cotton aphid numbers have decreased this week but are still being found in every program field with most of these infestations being found on the bottom sides of the mainstem leaves towards the top of the plant Beneficials are keeping most of these infestations in check. I should warn you though that if anyone elects to treat bollworms with a synthetic pyrethroid, at this time you will probably have to come back with another material to control aphids.

Boll weevil egg laying and feeding punctures in and around the city of Lubbock greatly increased this week. Percent punctured fruit in these fields are running from 25 to 30 percent total punctures with most being

egg laying punctures. As a whole, weevil punctures are still way down compared to last year.

Bollworm eggs are still being found in most program fields and are ranging from 1000 to12000 per acre with larvae ranging from 0 to over 3,000 per acre. Remember, the economic threshold for bollworms is 8000 to 10,000 per acre.

Whiteflies are being found in fields that are late planted and or stressed due to inadequate irrigation. Most of the worst infestations are being found adjacent to sunflowers.

WHITEFLY POPULATIONS BUILDING IN AREA COTTON

As mentioned above, whitefly populations are building in many fields over the county. The heaviest infestations can be found in fields that are stressed and are adjacent to sunflowers which are drying down. In addition, I have noticed substantial populations in fields that were planted in June.

The whitefly that we have is the banded wing whitefly and should not be confused with the silverleaf whitefly that has caused so many problems in the Rio Grande Valley and in Arizona. The adult banded wing whitefly is small in size and resembles little pieces of ash floating around when disturbed.

The basic life cycle of whiteflies is egg, nymph, adult with the nymphs going through a pseudo pupal stage before emerging as adults. Eggs are laid in the terminal area of the plant and will hatch in about five days. Newly hatched nymphs are very small and clear and disced shape. The nymphs will feed for about five days turn a yellowish green color and will enter the psuedo pupal stage. It takes generally 14 days to go from egg to adult.

Most of the areas heaviest whitefly populations are in sunflower and in stressed cotton adjacent to sunflower. With the increased acreage in sunflowers across the area, and with these flowers beginning to dry down I think the populations in cotton will continue to increase. To put the Lubbock County whitefly problem into perspective, most of the area fields have few whiteflies present even if the fields are adjacent to sunflowers. The key to finding heavy infestations is stressed cotton adjacent to dryland or stressed sunflowers.

The economic threshold that we are using at present is an average of 75 to 100 adult and nymphs on the fifth mainstem leaf down from the top of the plant. The reason we are using this high number is at these infestation numbers we are getting honeydew production. So far, the control measure that seems to working for us is a combination of Pyrethroind with Orthene for control of adults. We will be taking 8 day post treatment counts on Friday.