Estill, S.C., grower Doug Jarrell fights an ongoing battle with nematodes, losing too much yield, he says, to these microscopic critters that chew away at the root system of his cotton crop.

Working with peanut crop consultant James Thomas, Jarrell developed a soil map for most of the 1,500 acre farming operation he operates with his father B.L. Jarrell. The map shows fields categorized as low, medium and high risk for developing damaging nematode populations.

Using a simple off-on system developed by Clemson University researchers, he uses a simple variable rate application method to apply higher rates of nematicides in fields with higher risks of nematodes and applies less or none to fields with low risk of nematode damage. 

In fields with high risk of damaging nematode populations, he uses Telone II a soil-applied fumigant. Even in fields with Telone, he says he still used the standard five pounds per acre of Temik.

“In extreme cases, with really high levels of nematodes, we think we were losing as much as 400 pounds of cotton lint per acre. Over all our sandier fields, the ones at the highest risk of building up high levels of nematodes, we improved our yields by 250 pounds or so per acre, Jarrell says.

The shortage of Temik this year has created a need to change his nematode strategy a bit. In previous years, he only used Telone on fields in the high risk category. This year he will put Telone under fields in both high and medium risk categories.

On his cotton fields without Temik, he will use Avicta CompletePak seed treatments and will apply in furrow applications of acephate (Orthene).

Jarrell says the nematode plan developed by James Thomas was right on target. “There is no doubt using Telone on our nematode hot spots paid off. We monitor nematode samples closely and you can see the results in lower populations and in higher cotton yields,” he says.

Crop rotation is another big factor in managing nematodes. “We started growing peanuts in 2004, and noticed cotton yields went up in fields following peanuts. We had always known we had a nematode problem, but this really demonstrated how much yield we were losing,” he adds.