Art and science. Cotton farmers require equal portions of each to control weeds and manage cotton growth. With production costs soaring and cotton prices continuing to look for a bottom this year, an economical recipe might be even harder to concoct.
It takes a combination of long-range strategy and seat-of-the-pants flexibility, says Randy Boman, Extension cotton specialist, Lubbock.
“But don't skimp on weed control,” Boman says. “The weed spectrum in any particular field should be the main concern. Use transgenic technology where appropriate, but consider this option as a tool in a toolbox. Select the system that best fits a specific field.”
Boman says farmers planting conventional cotton varieties have “the routine arsenal of herbicides available, including yellow preplant materials — Caparol, Cotoran, Diuron, Dual, Staple — and grass herbicides.
“These can get expensive very quickly, especially if the weed spectrum includes weeds that can be controlled easily by transgenic weed control systems.”
For farms without hard-to-control weeds, Boman says, a conventional program may be the most economical. “A generic approach, however, using various weed control systems, may not be practical.”
Farmers should develop a specific program for a specific field, based on weeds present. “The Buctril/BXN system probably fits best in fields with cocklebur, devilsclaw, and morningglory problems,” Boman says.
“Pigweeds are not as easily controlled with Buctril, so a Roundup Ready system may be a better choice in fields with heavy pigweed infestations.”
Boman recommends growers develop specific budgets for each field, based on the weed spectrum, to determine the best choice: Roundup Ready, BXN/Buctril or conventional.
Boman says early boll set regulates plant growth and sets the crop up for early cutout and timely harvest. “The main criteria for deciding whether to use a growth regulator (mepiquat chloride) in the High Plains include plant size, early season square retention and continued growth potential,” he says.
“In the High Plains we normally do not produce overly large cotton because we can control plant growth with timely irrigation and accurate nitrogen fertigation through center pivot systems, especially LEPA. An exception might be furrow irrigation with extremely large amounts of water applied per irrigation.”
He says mepiquat chloride may fit best where fields have more than adequate soil moisture and producers wish to keep vegetative growth in check. Boman says that situation is especially prevalent north of Lubbock, in fields with excessive residual nitrogen, perhaps following a corn crop and in a year following severe drought and with ample moisture (such as row-watered conditions).
Earliness, he says, as with every other cotton production input, must be part of an overall management plan that seeks to produce the most lint per acre economically.
After all, he says, the bottom line is a profitable yield.
Editor's note: This is the fifth in a series on getting back to the basics in cotton production. Subsequent articles will deal with in-season insect control and other production practices.