Casteel: scout soybeans for compromised root systems, disease pressure
A Purdue University agronomist says the growing season for soybeans has been unusual with both wet and drought conditions.
Shaun Casteel, extension soybean and small grains specialist, says August and September will “make or break” soybean.
“If we don’t get the moisture here in August, we’re going to have a crop that’s just not going to retain as many pods,” he says. “Eventually if we have the heat and the dry conditions, we’re going to start losing leaves and you can’t recover fully from that. We need some good moisture, temperature, and sunlight.
He tells Brownfield farmers should scout for diseases.
“Over the last couple of weeks we’ve had some really dewy mornings and so I know we had a lot of fungicide applications so I would say let’s get out there and be scouting those now and see if we have frogeye leaf spot in particular,” he says. “Take a look 10-14 days after a heavy dew to see if there are any lesions showing up and then let’s get down and count the number of trifoliate nodes to see if we have a good 18-20 nodes, or were those fields some of the ones that got hit with the mid-season wet feet or dry conditions and there are only 14 nodes. This will help you anticipate what’s coming.”
Casteel says he’s seeing some “highlighter green” soybeans with compromised root systems, and the next 40 days will be critical for yield development.
Brownfield interviewed Casteel during the recent Purdue panel at the Indiana State Fair.