Michael Patterson is marshaling every strategy and resource to terminate glyphosate-resistant pigweed with extreme prejudice, but this does not detract at all from his grudging respect for this weed's capacity for wreaking havoc in Southern cotton fields.

If this weed were a football player, Patterson, an Alabama Cooperative Extension System weed scientist, would unreservedly assign it six stars — a six‑star player among noxious weeds.

Like any star player, it possesses staggering height, heft and speed. Growing at rates as fast as 2 inches a day, it can reach a height of 9 feet and a weight of 40 pounds.

That's precisely why Patterson and other weed control experts are so determined to stop it dead in its tracks.

Like any six‑star player, Palmer pigweed, also known as Palmer amaranth, must be shut down at the outset — in the case of row‑crop farming, in the weeks preceding planting — otherwise it will dominate the field.

Yet, size and growth rates do not account entirely for the weed’s destructive power. The females of this resistant biotype are able to produce up to 1.7 million seeds, averaging between 400,000 and 600,000 per plant.

"In a field of Palmer amaranth, roughly 40 percent of the plants may be female with the potential to produce a lot of seed, to grow really fast and to use lots of fertilizer and water, which makes it the perfect weed,” says Patterson.

As growing numbers of weed scientists and producers have learned through experience, it's all about dominance — dominating the weed before it dominates the cotton.

Dominance requires what Patterson has come to call the "two week herbicide program."   

The golden days when Roundup cotton once afforded farmers the luxury of a few over-the-top applications of glyphosate during the growing season to control weeds are long gone.

"If you're growing Roundup Ready cotton and you have a weed like Palmer amaranth that is resistant to Roundup, you can’t depend entirely on Roundup or, you're going to be out of business," stresses Patterson, who shared his strategies for pigweed control at the 2012 Wiregrass Expo, held in Dothan.

Soil residual herbicides — and for that matter, hooded sprayers — have once again become a standby of cotton production and one of the critical factors in securing dominance over the weed.