Sampling for scn
Fall is an excellent time to take soil samples from fields that will be planted with soybeans next year and have them tested for SCN – or soybean cyst nematode eggs. This also includes sampling corn fields that will have beans next year. The results will indicate if management decisions will need to be changed because SCN is the most damaging pathogen of soybeans in North America.
Greg Tylka is an extension nematologist at Iowa State University and explains how many soil cores you need.
"I like to have up to 20 soil cores collected from no larger than every 20 acres. But, if you have to, 20 cores from 40 acres is better than 20 cores from 80 acres," says Tylka. "The error involved in your sample results will increase the larger you sample the area."
The equipment you need is a soil probe, a bucket, and a plastic or plastic-lined soil bag. Sample the top 6"-8" of soil and take cores from within the root zone or from within the interrow area.
"Once a farmer or an agronomist collects a 20-core sample, first thing is they should put all those cores in a bucket and mix the cores up really well, break them up and then fill a soil sample bag," he says. "And then there are many options to send the samples to labs. Every state that produces soybeans probably has a university laboratory that will process the samples."
He says farmers can also get information and support from The SCN Coalition.