As he takes stock of the growing presence of Roundup-resistant pigweeds on crop fields from one end of the Tennessee Valley to the other, Charles Burmester is certain of one thing: The presence of this weed amounts to a game changer for row-crop producers.

The growing presence of this weed likely will mean significant changes in the way crops are produced in the Tennessee Valley — changes that will be both costly and time-consuming for producers.

Some have feared the weed's growing presence will dethrone the reduced-tillage cropping systems that have enabled producers to farm more profitably and in a more environmentally friendly manner. But that's not what concerns Burmester, an Alabama Cooperative Extension System agronomist, at least for the foreseeable future.

What concerns him is the effect this resistant weed's growing presence will have in eroding producers' ability to farm high yields on large acreages. In an era of comparatively low commodity prices, the high yields produced on relatively large acres have provided many of these producers with their sole source of profitability.

The use of Roundup Ready technology made this possible. This technology, which was based on the use of crops genetically altered to withstand over-the-top applications of Roundup, enabled growers to manage their fields more efficiently. This added measure of efficiency allowed them to farm larger acreages and, consequently, produce higher yields.

"The one way farmers have been able to survive is by increasing their acreage," Burmester says. "We were making less (in terms of commodity prices) but we could offset this by increasing acreage.

"In the past, you could farm a field 10 miles down the road because it didn't require a lot of equipment."

However, the loss of the Roundup Ready technology will deprive many producers of this crucial option. Likewise, farmers are going to have to be more focused on weed management issues than they have in previous years — a change that will require more time in the field and, with it, higher operating costs.

"It's going to require even better management to control the outbreak of these weeds," Burmester says. "They're going to have to go into these fields more often with hooded sprayers and other equipment to keep these weeds under control."

Consequently, that 10-mile trek down the rural highway to farm a 20-acre field will no longer be a viable option.

Back to that term again — game changer.

The emergence of this weed raises a myriad of other challenges — for example, what to do after corn harvest. A growing number of corn producers who have left cropland fallow after harvest have begun noticing a flush of resistant weeds when they prepare to plant other crops, such as cotton.

Burmester says some effective way must be developed to enable producers to control these weeds so as not to threaten succeeding crops.

With the loss of Roundup as an option, Tennessee Valley producers can still turn to an older arsenal of herbicides— the PPO inhibitors, Valor and Reflex, and residuals such as Diuron and Caparol. However, producers in the other parts of the South are dealing with their own weed-resistance issues, which have resulted in most of these products being in seriously short supply.

In the end, the growing presence of resistant pigweed will mean extra worry and expense for Tennessee Valley producers at a time when they least need it.

"This is a really difficult thing for them because they've got their system — one they've really been comfortable with — but this weed changes everything."