Auburn, Aug. 31---Until just a few years ago, many cotton producers considered weed control a slow, plodding process that was as tedious as it was time-consuming.

Worst of all, it could be expensive.

Many of the herbicides used to control weeds had to be applied directly to the soil in order to work -- a process requiring tilling, occasional disking and lots of heavy equipment, fuel and manpower. It was all the more difficult when producers chose to apply the initial round of herbicides during planting.

"The planting operation, by itself, is a slow process: a 5-to-6 -mile-per-hour, row-by-row routine," says Dr. Michael Patterson, an Alabama Cooperative Extension System weed scientist.

Adding herbicide spraying slowed the process even more.

There was not even a guarantee that the herbicides would work. Rainfall or sprinkler irrigation was required before the herbicides could be activated. Without rain or irrigation to move the herbicides into the weed germination zone, they would not provide control.

Yet, producers were not off the hook even when the herbicides worked. They still had to return to the fields several times throughout the growing season to cultivate and apply sprays directly to the weeds.

Fortunately for growers, controlling weeds in cotton got a lot easier in the mid-1990s with the introduction of Roundup Ready cotton.

Roundup Ready cotton, genetically altered to tolerate several sprayings of glyphosate, has afforded producers several key advantages scarcely imagined only a few years ago.

For starters, they no longer have to apply herbicides directly to the soil during or immediately following planting. Instead, they can wait until the weeds start popping up and adjust their spraying accordingly.

Also, the cotton’s genetic tolerance allows producers to apply the herbicide directly over the top of the cotton plants. This eliminates the need for early season mechanical weeding and sprayings targeted directly to the weeds.

What once required between six or seven different trips across the field often involves only two or three.

Glyphosate also requires less water for application and can be applied much faster than traditional post-directed chemicals.

Roughly 80 to 90 percent of Alabama cotton producers have adopted Roundup Ready varieties. But as many have learned, the variety they want to grow sometimes is not available with the Roundup Ready gene.

"Prior to the introduction of Roundup Ready cotton, if you spoke with 10 different growers you might learn they were growing 10 different cotton varieties that were chosen based on their own unique needs," Patterson says.

However, two new technologies, scheduled for commercial release in 2003, may provide alternatives to Roundup Ready varieties, he says.

Brawn is a herbicide effective on a wide variety of common weeds, including sicklepod and morning glory, and, like glyphosate, can be applied after the weeds emerge. However, its biggest advantage is that applications can be made to all cotton varieties, conventional and genetically modified alike.

Brawn is also effective against weeds at very low rates.

"We’re talking about one-tenth of an ounce per acre, which is pretty low – somewhere close to a teaspoon an acre," Patterson says.

However, like all new innovations, there is a downside associated with Brawn: Unlike, glyphosate, it is not effective against grasses, such as Johnsongrass and Bermudagrass.

A new cotton variety marketed under the product name Liberty Link, which is also scheduled for release in 2003, may provide producers with more options. Liberty Link cotton can be used with Liberty herbicide to control a wide variety of broad-leaved weeds and grasses in a manner very similar to the way Roundup Ready cotton is used with glyphosate – only more efficiently.

"Liberty Link kills weeds somewhat more quickly than glyphosate, and this cotton should be tolerant until first bloom," Patterson says.

Two factors probably will determine whether the Liberty-Link system is adopted on a wide scale, he says.

"The No. 1 factor will be overall cost. The second will be the yield and quality potential of the variety that contains the gene."