Cotton stalk destruction rules have changed a bit for the Lower Rio Grande Valley but the goal remains the same: prevent boll weevils from surviving through the winter.

Assuring a host-free period remains the number one defense in eliminating the pest from cotton production areas, says Webb Wallace, executive director, Cotton and Grain Producers of the Lower Rio Grande Valley, Harlingen.

For South Texas Zone 1, the host free period mandated by the Texas Department of Agriculture has always been from Sep. 1 to Feb. 1 of the following year. Originally, the law required that no live cotton plants be allowed during this period.

“With the advent of conservation tillage and chemical stalk destruction, the law was changed a few years ago to require that no ‘hostable’ plants be present during the host-free period,” Webb says. A cotton plant is defined as hostable if there are any squares, blooms, or green bolls.

“The first planting date of Feb. 1 worked well when the criteria was the presence or absence of live plants,” he says. “Once the rule was changed to presence or absence of hostable plants, local growers who make up the TDA Cotton Producer Advisory Committee for the Rio Grande Valley decided that although cotton may be planted on Feb. 1 and live plants may be present shortly thereafter, there is no justifiable reason for hostable cotton plants to be present during the month of February.”

For this reason, the committee recommended creation of a “first hostable date” of March 1 for Zone 1. The recommendation has now become law, with the LRGV the first zone in the state to adopt a “first hostable date” for cotton that is different than the first planting date.

A few other South Texas zones have already followed suit and created a “first hostable date.” TDA officials expect that adopting a first hostable date likely will become standard practice for all stalk destruction zones in the southern part of the state.

“We see no reason for hostable cotton to exist as early as Feb. 1,” Wallace says. “Moving that date to March 1 gives TDA extra time to enforce the regulations and to treat the illegal cotton.”

He says typically any hostable cotton still present in February was abandoned. Previously, that cotton would have been legal again on Feb. 1. “Having an extra month added to the host-free period gives TDA officials more teeth to enforce compliance on abandoned fields.”

For 2007 only, Stalk destruction deadline for Zone 1 was extended until Oct. 4 because wet conditions limited access to fields. “We never like to extend the deadline,” Wallace says, “but conditions were so wet we had no choice this year.”

As of late September, the LRGV boll weevil eradication office reported about 3000 acres of cotton still hostable in the area and being sprayed for weevils.

“Although most of our cotton was out by mid-September, growers have been waiting for the wettest areas to dry out. Even in late September, some growers were still harvesting cotton in mud. We’ve had almost two weeks without rain now, and all those areas are just about finished.”

“The October 4 deadline should not be hard to meet except for fields with lagoons or very low areas,” Webb says. “On those fields, growers need to apply for an individual extension with TDA.”

Spraying 2,4-D has become the preferred method to eliminate hostable cotton in the area. “Most of our acreage is sprayed with 2,4-D,” Wallace says. “But even with 2,4-D, wet conditions still present a challenge. There are only certain areas where it can be applied safely by airplane. A lot of fields are too close to houses or other crops. In some cases, we can’t even use 2,4-D with ground rigs because of similar concerns.”

Other options include shredding stalks, chiseling, or using stalk pullers. “Shredding buys time until farmers can get back with a disk, stalk puller or chisel plow,” Wallace says.

One trip with a plow is usually adequate. “We normally need two applications of 2,4-D, about one month apart, to eliminate all hostable plants,” he says.

Valley farmers have done “a good job with stalk destruction the past two years. Weather was dry and they got a good start. This year wet conditions have set us back, but everyone is glad the eradication program is treating late cotton. Without the program, there would have been so many weevils it wouldn’t be safe to walk into a cotton field this year.”

email: rsmith@farmpress.com