VIDALIA — While the drought conditions over the past three months have left area crops damaged and in need of water, the high heat and lack of rain is also stirring up problems below the soil.

Concordia Parish cotton, soybean and corn farmers are now dealing with nematodes, a problem LSU AgCenter agronomist Charles Overstreet said is intensified in drought conditions.

“A nematode is a microscopic, worm-like animal that lives in the soil,” he said. “They eat away at the plant’s roots.”

Overstreet said the nematode problem has become prevalent in the middle of Louisiana running through Alexandria.

“Concordia is having some major problems with them just like the rest of the affected area,” he said.

Overstreet said nematodes are always a problem for area farmers, but the drought conditions make their damage more visible.

“They are prevalent in all weather, but during drought times the plants are already stressed, so the additional stress of the nematodes makes things worse,” he said. “The plants are eaten away at the roots, and then they are stunted, small (plants) have less of a yield than they normally would.”

Overstreet said there are two types of nematodes that cause problems in Louisiana, the reniform nematode and the root-knot nematode.

“The reniform attacks cotton, soybeans and sweet potatoes,” he said. “The root-knot attacks cotton, soybean and corn.”

Overstreet said if a nematode problem goes unchecked in a field, farmers can experience significant yield loss.

“If you look out at your crop and see that it has an ‘up and down’ pattern, meaning there are a lot of stunted plants, you may have nematodes,” he said.

Overstreet said one way to help deal with nematodes is the spraying of nematicide on crops.

“There are a few varieties of soybean that have a resistance to root-knot nematodes, but there are no varieties of any crop with resistance to reniform,” he said. “The nemanicides work to help get rid of them, but they tend to work best on areas with lower levels of nematodes.

“You want to spray in areas where their population is high enough to cause damage, not the whole crop,” he said. “It also works best, especially with cotton, if the nemanicide is on the seed before it is planted.”

While nemanicides are effective, Overstreet said the best way to avoid a nematode problem is crop rotation, because once they are in an area, they do not go away.

“For years we would plant cotton crops without rotating them, and we were experiencing some major problems with nematodes,” he said. “The cotton price went down over the years, and farmers started using those fields for corn. They found that a year or two of corn gave them an increase in yield.”

Overstreet said rotating the field to corn is a good option, but root-knot nematodes can cause problems with corn.

“If you have root-knot nematodes, swapping to milo or grain sorgum is also an option,” he said. “If you can, try and go with corn, because the crop is worth more.”

Farmers need to stay on the lookout for any problems with nematodes, because finding them in time is crucial to minimizing damage, he said.