Plan for Future Yield Increases Now;
Check Soybean Roots for Nodulation

Soybeans need nitrogen — and lots of it — to reach their full yield potential. That means soybean roots need to be properly inoculated with the right strain of rhizobia to effectively and efficiently provide the nitrogen needed for maximum yield.

"Conducting in-field evaluations of soybean root nodulation can provide growers insight on how to increase yield potential the next time soybeans are planted in that field," says Jim Beuerlein, technical consultant to Becker Underwood and retired Ohio State University Extension agronomist.

Evaluating Nodulation
Soybean nodulation checks require only a few basic tools — a spade, a bucket of water and a sharp box cutter or blade — and the knowledge of what to be looking for. Conduct enough checks to provide a good representation of what's taking place in the entire field. Beuerlein offers the following tips for effective soybean root nodulation evaluation.

Timing:

• Start checking plants 40 days following emergence and until pods begin to fill.

• Use a spade to dig up as much of a plant's tap root and lateral roots as possible. Plants 6 to 8 inches in height will have most of their roots within the top 10 inches of the soil surface.
• Do not pull the plant as this can cause nodules to be separated from the roots.
• Carefully remove soil from around the root system.
• Soak roots in a bucket of water and gently remove the remaining soil.