From the Coastal Plains of the Carolinas to the High Plains of Texas, farmers are facing or trying to avoid the nightmare of herbicide resistant weeds and grasses that threaten to upset management practices and alter enterprise choices, chemical selection and tillage systems.

Palmer amaranth, also known as pigweed, is the most commonly discussed or just plain cussed weed across the Sunbelt, but a host of others, nearly 100 separate species, show resistance to one or more classes of herbicides.

Virtually all crop gatherings — from the Beltwide Cotton Conferences to regional expos to county production meetings — now include at least one weed specialist discussing the threat of herbicide resistance and offering recommendations on how to avoid the problem or how to manage it once it establishes itself on a farm.

Avoidance is the best, least costly, approach, specialists say, but in some areas the mule has left the barn and farmers are left trying to reclaim cropland from heavy weed infestations.

Alan York, retired Extension weed specialist from North Carolina State University and now a consultant, speaking at the recent Bayer CropScience-sponsored Southwest Crop Consultants Conference in Austin, Texas, said some areas in the Southeast have been “overwhelmed.”

Most farmers, York said, are not as prepared for resistance management as they might think. “If they get into a bad problem, they can quickly get overwhelmed.”