Jacobsen said Cheminova will continue to support efforts of Texas AgriLife Extension and the Texas Department of Agriculture to secure the exemption. “We also will look at T-band variations, the effect of irrigation timing, potential to apply pre-plant and try to get a better feel for moisture demand,” he said.

Isakeit said he’s hopeful that a problem that was identified as far back as 1872 may be near a solution. “In 1872, a farmer reported ‘poison soil,’” he said. “In 1888, a plant pathologist identified the fungus and a wide range of hosts. He recommended crop rotation.”

Crop rotation may provide some benefit but the fungus apparently remains in the soil and remains a threat to cotton production. Topguard may diminish that threat.