Midseason Soybean Checks Can Inform Next Season
JOE BUNCK
EVEREST, KAN.
Farmers can gather field intelligence now to inform and hone product selection and management approaches for next season.
As soybeans enter the mid- to late-season growth stages, farmers may notice yellowing leaves, called leaf chlorosis, which can indicate low fertility, disease or restricted root growth. To determine a cause, evaluate fields for any condition that can jeopardize nutrient uptake by the roots such as soil compaction, water-saturated soils or insect feeding. Some soybean diseases like sudden death syndrome and brown stem rot can also resemble nutrient deficiency symptoms.
Throughout the growing season, soybean plants acquire nutrients from the soil and through nitrogen fixation in the root nodules. Pod fill is a period of high nutrient demand, and if the soybean plant cannot absorb needed nourishment to support seed development the plant will remobilize nutrients from the stems and leaves. As nutrients are reallocated away from the leaves they tend to yellow, which is an indication of nutrient deficiency.
Channel Seedsmen conduct field evaluations to help farmers determine what conditions may be causing soybean leaf chlorosis. They assess the agronomic needs on farmers’ fields to help plan a fertility program for the next season’s crop and recommend seed products that are an ideal match for the anticipated growing environment.
As the end of July approaches in Kansas farmers should evaluate soybean for the presence of seed and pod feeding insects, such as green stink bugs, grasshoppers, podworms, and bean leaf beetles. Additionally late season diseases such as Frogeye leaf spot, and Cercospora leaf blight are often observed. These insects and diseases can be controlled with insecticides and fungicides if they reach economic thresholds.
The next few weeks of observations and notes from Seedsmen can help provide a picture of fall yield potential and set the stage for next season’s product selection. Visit channel.com to learn more about the Channel Field Check Up Series and to access more agronomy tips and insights. ∆
JOE BUNCK: Channel Technical Agronomist