The Wisconsin Soybean Marketing Board and the University of Wisconsin-Madison are continuing their offer of one free soil test per farm to help Wisconsin soybean growers monitor their fields for the soybean cyst nematode.

The soybean cyst nematode attacks soybean roots. It has become one of the crop”s most serious pests across the state, according to Ann MacGuidwin, a nematologist in the College of Agricultural and Life Sciences. The nematode can reduce soybean yields even when plants appear normal above the ground.

“The only way to know for sure if the nematode is limiting yields is to run a soil test,” MacGuidwin says. “A soil test also shows the pest”s population density in a field, which is important for deciding whether or not to plant a soybean variety with resistance to the nematode.”

Since Sept. 1, many individuals have taken advantage of the free nematode test. Those who have not already done so are encouraged to submit a sample to MacGuidwin”s lab for analysis.

To collect a soil sample, growers should use a soil probe or hand trowel. Collect 10 to 20 soil cores 6 to 8 inches deep in a zigzag pattern throughout 10 to 20 acres of a field. Dump cores into a bucket and mix thoroughly. Place approximately 2 cups of mixed soil in a plastic bag and label it. Include your name, address and phone number, sampling date, the number of acres represented in the sample, crop history, and name, location or number of the field sampled. Samples can be collected in the field at any time. However, the best results are obtained from unfrozen soil.

Growers can send a sample by second class mail to: Prof. Ann MacGuidwin, Room 495 Russell Labs, University of Wisconsin-Madison, Madison, WI 53706. For more information, contact Ann MacGuidwin at (608) 263-6131, aem@plantpath.wisc.edu or Adam Kaszubowski at (608) 265-1155, awk@plantpath.wisc.edu.