CURRENT CROP CONDITIONS
The area cotton crop is continuing on schedule with program fields ranging from 10 true leaves to bloom and boll. We have quite a mix of cotton out there with fields that entered bloom with 11 nodes above first position white flower to seven nodes above first position white flower. Most of the dryland went into bloom at seven nodes above first position white flower. Overall, we have a better crop compared to years past. The biggest problem I see so far is with the row water fields being irrigated too late. It has been my experience that when you are at seven nodes above first position white flower, and you are just starting to irrigate then you will generally cut out too early unless you can put on two inches of irrigation in 48 hours. I do not have a single producer in the scouting program that can row irrigate that fast.

WHAT THE SCOUTS ARE FINDING
Pest pressure has changed dramatically since the last newsletter with bollworms dominating the scouting reports. Lygus bugs are still being found in very low populations in most program fields. I really believe this pest will be of concern in our area in the next few weeks, especially in the late planted cotton. Cotton aphids are still being found in the terminal area of plants in most program fields and are starting to move to the undersides of the leaves in a few locations. Cotton aphids will probably be a real concern with all the pyrethroid applications going out for bollworm control.

Beneficial insects are still keeping this pest in check for the most part, but fields that have been treated with a pyrethroid have little or no beneficial insect activity. Bollworm eggs are still being found in most program fields and are ranging from 500 to 2000 per acre. As a whole the egg lay has declined across the County. Larvae are ranging from 0 to over 40,000 per acre. We have several different scenarios going on with this pest. Several program fields have been experiencing chronic infestations of this pest. Square sets in blooming cotton have dropped from 95-100 percent down to a 65 - 70 percent square set. Worm counts in these fields have not exceeded 5,000 worms per acre but have a total of over 20,000 over the past 14 days. In these cases we will have 2000 medium worms per acre with 3000 small worms per acre. Most of the chronic infestations are occurring in fields that are not very lush.

We have fields that are experiencing acute infestations of bollworms with infestations ranging from 20,000 to 40,000 per acre. Most of these fields are lush with high plant populations and are in full bloom. I believe that the worms are worse in these fields due to the supply of small squares available to the worms. Most of the plants in these fields have small third fourth and fifth position squares on main stem nodes five six and seven that provide a protected environment to get infestations started.

I believe that if this current weather pattern holds with lower temperatures and winds out of the South East we will continue to have this kind of worm pressure. I do think that we could alleviate some of this pressure with some hot temperatures and lower humidity. Basically, we need temperatures above 95 degrees and winds out of the South West.

* 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.

Since pyrethroids are not more effective than organophosphates or carbamates for boll weevil control, but are more effective for bllworm control, they should be saved for bollworm management. We do not recommend using pyrethroids for boll weevil control alone or for early season pests because increased use may contribute to the development of resistance to pyrethroids. Bifenthrin suppresses spider mites when used for control of bollworms. The use of synthetic pyrethroid insecticides may increase cotton aphid numbers.

PEST MANAGEMENT CONTROL STRATEGIES WITH BOLL WEEVIL ERADICATION

First off, we need to clear up some misconceptions that I hear on a daily basis while talking to producers. The first and most popular misconception is a spray schedule. The foundation is not going to spray your field every seven days once your field is targeted for application. The next misconception is that the foundation is not spraying your entire area once one weevil is found.

There is a simple set of events that has to happen for your field to be treated by the Eradication Foundation. Before Monday July 8th, the Foundation was using as their trigger one weevil per field. The foundation would then treat that field and every field within 1/4 of a mile. After Monday July 8th the Foundation is still using a trigger of one weevil per field. The Foundation will then treat that field and the adjacent field.

BOLLWORM CONTROL STRATEGIES

Bollworm control decisions are really not that difficult if you simplify matters (although you can always over simplify). The information that you will need to make a decision are: 1. A realistic population estimate, both plants and larvae; 2. Will coverage be an issue (how tall and lush is your cotton); 3. Will you use a ground rig or plane; 4. Do you want to conserve beneficials; 5. The price of the material.

If you want to conserve beneficial insects then you can use products such as Tracer, Larvin or Bt products. Coverage is crucial for these products and if you have to use a plane or your cotton is lush then I would not recommend any of these products. Another consideration is pest population. If you have more than 10,000 worms per acre then I would in most cases not recommend these products. If coverage is not a problem and you can use a ground rig and you do not have a blow out population then by all means use these products. However, some of these products can be pricey.

If you have lush cotton and have to apply by air and you have more than 10,000 worms per acre then use a pyrethroid. For the most part they are cheap and provide excellent control. These products do have a downside. You will dramatically reduce your beneficial populations and can possibly flare cotton aphids well past economic threshold.

As a side note, if you are scheduled for a boll weevil application by the Foundation and you are going to spray the field for bollworms, you can cancel the Foundation application by applying either the pyrethroids or Methyl Parathion on your bollworms. However, you must make two applications within seven days. I do not see the benefit in this strategy either economically or biologically. Two applications of Methyl or a pyrethroid within seven days will destroy your beneficials and you have to pay for both applications. In addition, two applications of a pyrethroid in seven days will up your chances of flaring aphids considerably. In my opinion, take the Foundation application and make your pyrethroid application. You will save money.

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