Some of our early planted cotton will be producing the first square very soon and thus enter a growing stage that is of critical importance as yield potential is being determined.

This time of development for the cotton plant is critical, as by the time the cotton plant begins to bloom, 80 to 90 percent of crop to be harvested is on the plant.

Currently our cotton crop is growing through a stage of development in which the roots grow faster than the plant parts aboveground. A young taproot may extend 6 inches into the soil by the time the first true leaf is visible. Then soon after the first true leaf appears, the roots begin developing an extensive lateral system.

Roots grow where moisture, oxygen and temperature are optimum. As these three factors decline, root growth slows and, as a consequence, the plant takes up less water and nutrients. This would explain why recent very wet conditions in some parts of the county, actually stressed the young cotton plants, as too much water starved the plant of oxygen.

Before the reproductive stage is reached in the cotton plant, the primary insect pests of cotton are the thrips complex and the aphid complex. Recent research has shown that cotton is extremely susceptible to thrips damage before squaring. By the time producers notice damage (crinkled leaves, leaf margins curling upwards), the economic damage has been done.

In general, weed control is critical during the first six weeks of the season. Although having a few weeds in a field generally has little effect on production and harvesting, having many weeds can cause severe problems. Research has shown that if weed competition ends at four weeks, little yield is lost, however beyond that four-week time frame, competition from weeds begin to reduce cotton yields.

To address critical management issues during this time of crop development, the Gulf Coast Cotton Management Workshop will be held on Wednesday, May 12, with the focus on "First Square to First Bloom." The workshop will be held at the Texas AgriLife Research and Extension Center at 10345, State Hwy 44, just west of the Corpus Christi International Airport.

Registration will begin at 8 a.m. followed by the program at 8:30 a.m. and will conclude by 11:30 a.m. Workshop topics and speakers will include the following; Overview and Current Crop Conditions by Dr. Juan Landivar, Resident Director of the Research Center, Physiology of Cotton Plant by Dr. Carlos Fernandez, AgriLife Research Scientist, Managing Fertility, Plant Height, and Square Retention, by Dr. Dan Fromme, Extension Agronomist, Insect Management by Drs. Roy Parker, Extension Entomologist and Mike Brewer, AgriLife Research Entomologist, and Using Computer Online Tools to Help Manage Crop by Jeffrey Stapper, County Extension Agent - Nueces County, and Carlos Fernandez.

Participants in the workshop will be awarded CEUs toward their Pesticide Applicator and Certified Crop Advisor Licences.

This workshop is one of a series that will be held throughout the growing season this year. The workshop is being sponsored by the Texas AgriLife Extension Service and Texas AgriLife Research. More details are available from the Nueces County Extension Office at 361-767-5223.

Educational programs of the Texas AgriLife Extension Service are open to all people without regard to race, color, sex, disability, religion, age, or national origin. Individuals with disabilities, who require an auxiliary aid, service or accommodation in order to participate in any of the mentioned activities, are encouraged to contact the County Extension Office eight days before all programs for assistance.

Jeffrey Stapper is the Agricultural and Natural Resources Agent for Nueces County. Readers may contact him at (361) 767-5217.