CURRENT CROP CONDITIONS
The area cotton crop is continuing on schedule with program fields ranging from full bloom to cutout. Most of the program fields will be less than five nodes above uppermost first position white bloom by next week. Most fields are still being Irrigated at this time. Most of the program dryland acreage is finished. We really could have used a substantial rain last week.

WHAT THE SCOUTS ARE FINDING
Since last week, the pest pressure has increased for most producers. Cotton aphids are ranging from infestations located in the terminal and on squares of the plant to over 50 per leaf. Most of the heaviest infestations are occurring where a pyrethroid was applied 12 to 14 days ago. Beneficial insects are hit and miss in most of our fields. In some cases we are seeing benefit from ladybug adults and larvae and in other situations this beneficial insect is hard to come by. Most of the producers that have treated for aphids have used 0.8 ounces of Intruder through both ground and aerial applications. I do believe that the 0.6 ounce rate of this product will give satisfactory control of aphids. I will try this rate by the time the next newsletter is written.

Bollworm eggs are still being found in most program fields and are ranging from zero to 3000 per acre. Larvae are ranging from 0 to 10,000 per acre. In fields that have cutout the plants are literally shedding the worms that are feeding on the small squares and bolls.

In the cotton with the higher yield potentials, I am still using a threshold of 8,000 to 10,000 worms per acre. Most of these fields are lush and the bottom bolls are still soft and vulnerable. In fields that have cutout early due to stress, I have raised the threshold to 10,000 to 20,000 worms per acre. In most of these fields, there is very little small fruit left for the newly hatched worms to feed on.

Beet armyworms were found in economic populations in the Eastern and Southern portions of the County on Tuesday. Infestations were ranging from less than 5000 per acre to over 45,000 per acre. In addition to larvae, we are finding egg masses in most program fields. These infestations thus far are a little different than we experienced in 2000. In 2000, you could easily find where the egg mass hatched and it took a little longer for the larvae to disperse. This year, the infestations are more in line with boll worm infestations in that the larvae are dispersing very quickly and are immediately feeding on small bolls and squares.

BEET ARMYWORMS HAVE ARRIVED IN LUBBOCK COUNTY.
As you may or may not know, beet armyworms are present in many area fields. There is really no rhyme or reason to these infestations. You can find economic infestations in lush drip irrigated fields and in poor drought stressed fields as well.

First of all, where did all these beets come from? I do not really know . I do know that several factors are conducive to beet armyworm out breaks such as mild winters; late planting; delayed crop maturity; heavy early-season organo-phosphate or pyrethroid insecticide use; prolonged hot, dry weather conditions; presence of beet armyworms prior to bloom; and weather conditions that support long-distance migration.

Other characteristics of high risk fields include, sandy and droughty soils; skip-row planting; fields with skippy, open canopies; drought stressed plants; and fields infested with pigweed. The likelihood of a heavy outbreak increases as more of these factors occur in a given location. However, when beet armyworm populations are high all fields are susceptible. With that said, I do not know where these infestations came from. I will chalk this up to a migrating population.

Lets get to the nuts and bolts of this problem which includes scouting and control. In my opinion, several mistakes are usually made when scouting for this pest. The biggest mistake would be the use of "hits" to determine when to treat. A hit should be defined as a plant that has egg masses present and not a plant that has been chewed up by the hatching larvae. A person using this method tends to hunt for damage and never really stops to see how many larvae are present. Keep in mind, that with the hot temperatures we are experiencing you can expect some mortality. The other mistake I am seeing is the over estimation of populations. You need to examine a random population of plants and not just examine plants around the "hits". For the most part, scout for this pest as you would for bollworms. The leaf feeding damage is readily visible which has a tendency to excite people to make an overestimation of the population. In order to make an informed decision you need to calm down, have an accurate plant population and use your plant population estimate to estimate the number of worms per acre. Divide the number of plants checked into the number of worms found and multiply by your plant population. Treat when you have from 10,000 to 20,000 small worms per acre. Now I know I used a wide range as a starting point, but remember the rules used for bollworms. If you are past cutout and your cotton is stressed and has shed all the small fruit then you can raise the threshold. This brings me to another mistake I am seeing. You cannot kill a high percentage of large beet armyworms with the products available. Estimate your population on small worms (less than ½ inch in length). Do not use the bollworm mentality of control which is to expect 85% to 100% control. Expect at best 65% to 80% control and be happy. If this pest gets established in this area, you should expect to treat several times.

What should we use to control this pest? We have several new and proven products for this pest. The newer products are Intrepid and Steward . These products were tested in 2000 and provided excellent control. Intrepid is a newer formulation of Confirm and provides good residual control at the higher rates. Steward preformed well in 2000

and has the added benefit of controlling bollworms. The remaining products in the table provide some measure of control but are inconsistent in my opinion.
If you have to treat for both bollworms and beet armyworms I would suggest using a mixture of a pyrethroid with any of insecticides listed below. Although Steward does have activity against bollworms, I would probably go with a lower rate of this product mixed with a low rate of a pyrethroid.

Suggested insecticides for beet armyworm control

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