Many Mississippi cotton producers have nematode problems that are costing them yield and dollars, says Tom Allen, yet they often may not know they have the pests, or if they do they may not be correctly managing for them.

“I’ve been beating the drum about this,” he said at the annual Mississippi State University Producer Advisory Council meeting, attended by producers from counties in northern Mississippi.

“The best way to manage nematodes is to be as proactive as possible,” says Allen, who is associate professor with an Extension and research appointment at the Delta Research and Extension Center at Stoneville.

“And the first step in doing that is to sample, sample, sample, sample — I can’t emphasize this enough. This is how you find out where you have a problem.

“I know analysis of a soil sample will cost $11 per sample at the Mississippi State laboratory, but it’s worth it. If you have a nematode problem in your cotton fields, you could easily be losing the cost of the soil sample in yield.”

Allen says growers should be aware that different labs have different methods of reporting the soil sampling results when it comes to the number of nematodes per amount of soil analyzed.

“The Mississippi State lab looks at a pint of soil, which is equal to almost 500 cc of soil; other labs may use 250 ccs, and some use 100 ccs. So, when you get your lab report, make sure you know how much soil was used before you consult a nematode threshold. Then you can calculate your numbers and determine how those fit into the published nematode thresholds.”

Also, he notes, numbers will differ for samples taken in the spring, mid-season, or fall, as well as for different soil classifications. “Keep in mind that root-knot nematodes prefer sandier soil, while reniform nematodes prefer soil with more silt characteristics.”