The pest is showing up in early-season soybeans. Current numbers don't necessarily warrant treatment, but the pests can double in population in only a few days. Scouting is the only way to stay on top of them.
Farmers need to pay particular attention to corn fields that were hit hard by the disease in 2021 and have rotated back to corn this year. Fields with high levels of residue are more susceptible. Beware of heavy rains just prior to canopy too.
“This is the earliest we’ve reported tar spot in Iowa,” says Alison Robertson, Iowa State University professor. She says the early detection could be due to the Tarspotter app. Here's how it works.
Visual symptoms of red crown rot often show up in soybeans between R3 and R7 growth stages. The foliar symptoms — interveinal chlorosis and necrosis — are nearly identical to sudden death syndrome. Double-digit yield losses are not uncommon.
Too much rain? Too litle rain? Cool temps? Blazing temps? How's the weather treating crops on your farm. Let us know — and be sure to send us photos, too.
