As the cotton harvest continues, it is important not to forget about destroying those cotton stalks as soon as the crop has been removed from the field to aid in reducing costs for the Boll Weevil Eradication Program.
This year, there has been a 90 percent reduction in the number of boll weevils caught in the zone compared to last year. Good progress has been made on this front, so lets keep the weevils on the march and out of town for good.
The Chairman of the Zone 2 Cotton Producer Advisory Committee has sent a request to the Texas Department of Agriculture to extend the cotton stalk destruction deadline for Zone 2, Areas 1, 2 and 3. Citing weather conditions that delayed cotton planting at the beginning of the season, along with seasonal weather that delayed crop maturation, the committee chairman is requesting the deadline for these areas with a Sept. 1 and Sept. 15 deadline be extended to Sept. 22.
This change in deadline will be in effect for the 2010 crop year only.
Counties affected by the extension include: Jim Wells, Kleberg, Nueces, San Patricio, Duval, Webb and the southern portions of Bee, Live Oak and Aransas counties.
In its native habitat, cotton is a perennial shrub that may survive for many years. The perennial habit of cotton allows it to re-grow following harvest, providing the potential for development of hostable fruit (squares and bolls) for boll weevil feeding and reproduction. Under good environmental conditions, cotton plants can generate hostable fruit in three to four weeks.
When field conditions and weather are favorable for tillage, stalks can be shredded and then disked to destroy the intact plant. Stubble stalk pullers can also be used to uproot the stalk. These mechanical methods are generally successful, but some stalks may survive these operations. Also, many growers are implementing reduced tillage systems that do not allow for primary tillage operations, causing producers to evaluate new methods for stalk destruction.
Several herbicides have been registered for cotton stalk destruction. Herbicides available include, but are not limited to 2,4-D (ester and salt formulations), several dicamba products (Weedmaster, Clarity, Banvel), and Harmony Extra (thifensulfuron-methyl + tribenuron-methyl). For these products to be legal for cotton stalk destruction, the label must contain a section addressing "crop stubble" or specify cotton as the target pest following harvest.
Based on most recent field research, it appears the low-volatile, amine salt formulations are equally as effective as the ester formulations for cotton stalk destruction, and minimize problems associated with off-target drift.
The first application should be at the rate of one pound of active ingredient/acre (eg. 1 qt. of a 4 lbs. a.i./gal. formulation). Generally, a second application of 0.5 to 1.0 lb. a.i./acre will be necessary for control of any live stalks and emerged cotton seedlings.
To obtain optimum results, cotton stalks should be shredded (six- to eight-inch height) and the spray application should be made soon after shredding. To achieve optimum effectiveness, some growers have mounted spray booms directly on their flail shredders and are banding their herbicide during the shredding operation, and achieving excellent results.
As we work to wrap up another cotton harvest, it is important to remember that without an effective cotton stalk destruction program here in South Texas, boll weevil eradication cannot be accomplished.
Jeffrey Stapper is the Agricultural and Natural Resources Agent for Nueces County. Readers may contact him at (361) 767-5217.