Have you tested your fields for soybean cyst nematode (SCN) lately? If not, it may be time to put a shovel in the ground and do a soil analysis.
In this episode of the Soybean School, Huron Commodities agronomist Wayne Wheeler provides tips on how to quickly assess whether or not the tiny root pest is robbing yield in your fields and what you can do about it.
In a 2014 Huron County soil survey, 50% of the samples tested positive for SCN, confirming it is indeed on the move and gaining a foothold in new regions of Ontario. Depending on egg mass levels, the pest can cut yields by 5% to 100%.
SCN tends to have its greatest impact in dry years like 2016, says Wheeler. He explains that the nematode, a microscopic worm, impacts the water flow within the plant. “When that happens in a drought year, you have that one plus one equals five scenario. If we had adequate rainfall there would still be impact on yield, but not nearly as great as in a drought year.”
When you suspect SCN, Wheeler says it’s important to dig up plants, look for egg masses on the roots, and have a lab do a soil analysis to determine egg levels.
“We’ve seen fields up here as high as 24,000 eggs per 100 grams of soil. Even when you plant an SCN-tolerant line, when you get over 10,000, you can still have an impact on yield,” explains Wheeler. “Even at 1,000 eggs on sandier soils where you are more prone to drought, you could have yield loss.