In this issue:
General Situation
Important Terms and Concerpts in I.P.M.
Upcoming Events

General Situation:
Essentially all cotton in our area has cutout (4 or fewer nodes above white flower), some of the better watered fields are still trying to maintain squares. But even these well watered fields are shedding the newest bolls as soon as the flower dries, yet they have retained a major portion of the fruit set. We are beginning to find open bolls (very few) in fields with marginal water. Aphid numbers are generally on the decline, even where not treated. Lady beetle and lace wing larvae populations are increasing. Bollworm egg laying continues, although survival is down, worm populations ranged from zero to 15,600 (reports of over 20,000 from consultants) worms per acre. Where worm populations are high and aphids present we have recommended treatment.

Leverage has provided good control of both worms and aphids where treatments for both were required. Other combinations of a pyrethroid plus furdan (or another aphid control product) have also provided good control. There have been some reports of control failures with various products under various conditions.

The Texas A&M University System, U.S. Department of Agriculture, and the Commissioners Courts of Texas Cooperating

The economic threshold is a key IPM decision-making tool. Thresholds are based on considerable amounts of research and/or field experience. If the economic threshold is approached, but not reached, do not apply a pesticide at that time. Instead, re-scout the field within a few days to determine the status of the infestation. Pest populations can decline naturally due to mortality from natural enemies and unfavorable weather conditions. Also, many pests, such as caterpillars, change from an active feeding (larva) to a non-feeding stage (pupa) during their development. Such changes will often produce a natural decline in infestations as pupation occurs.

Why Aren't There ETs Available for Every Pest?
ETs are notoriously difficult to determine. At first glance, an ET would appear to be a straightforward, cost-benefit relationship involving control costs and market values. However, if you consider the influence of multiple pests on a crop , injury per individual pest, crop response to injury at various stages of development, varying climactic conditions, nutritional stresses, varietal differences, the purpose for which the crop is grown and fluctuating market values, then you can see how ETs might be slow in development and constantly changing.

Who Needs ETs?
We all do! ETs are the most effective method of determining if control is justified. Also, if pesticides are to be used, ETs help determine timing of pesticide applications. ETs are available that work quite well in maximizing the effectiveness and minimizing the number of spray applications for many pests. Some are still under development and many more need to be developed. ETs represent a giant step forward in timing pesticide applications when compared to calendar or preventive spray schedules.