Ask the Agronomist – Top Questions & Answers for Soybeans

Soybean field and soy plants in early morning.

If you’re looking to move your soybeans to that next yield level, ESN is a tool that can help you achieve that goal. As a legume crop, soybeans can fix their own nitrogen from the atmosphere, but under certain conditions, nitrogen may be a limiting factor. Keep reading as we discuss the top three questions we have received from growers about soybeans, answered by ESN agronomists.

Q: Will ESN boost yields on irrigated and dryland soybeans?

A: We have done some research on ESN applications on soybeans in recent years. This Mississippi study demonstrated how ESN can increase yields in irrigated soybean production. ESN applied at an optimum rate at V4 or R1 growth stages increased yields by five or seven bushels per acre, respectively.  An Illinois study in rainfed soybeans observed yield increases ranging from 3.4 to 4.7 bushels per acre when ESN was applied from planting to onset of flowering (R1 growth stage).

Q: What is the recommended rate and timing of application for ESN in soybeans?

Q: Previous research has shown that soybean plants may cease forming nodules if there is a large amount of available nitrate in the soil. For this reason, soluble forms of nitrogen are not recommended for application until after flowering. Using ESN should allow for more flexibility in this type of application because of the controlled-release mechanism.

Our current recommendation is to apply ESN somewhere between the V4 and R1 growth stages in southern regions with long growing seasons and warm summer temperatures. This allows enough time for the ESN capsules to hydrate, start releasing urea into the soil, and for that released nitrogen to convert and move down into the soil to the soybean root. Typical rates have been in the range of 40 to 80 lbs N per ac as ESN.  For northern regions with shorter growing seasons and cooler soils, ESN may be applied as early as planting time or anytime during vegetative growth prior to flowering.

Q: Will the nitrogen in ESN cause soybean plants to cease forming nodules?

Previous research has shown that large amounts of soil nitrate-nitrogen can inhibit nodule formation and efficacy in soybean plants. For this reason, soluble forms of nitrogen are not recommended for application until after flowering. Using ESN allows for more flexibility in this type of application. ESN’s controlled N release can provide additional nitrogen to soybean plants during flowering and pod set without inhibiting N fixation by nodules, resulting in higher yields. ESN protects N from loss inside its unique protective coating and supplies N to the crop when it is needed. The result is increased soybean yields and improved N-use efficiency.

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Disclaimer: This information is not intended to be complete or detailed use recommendations for all geographies, crops, or applications. User assumes all responsibility for proper use and handling for specific geographies, crops, and applications. Please consult ESN recommendations and/or your Nutrien ESN representative for complete recommendations for use. Consult ESN recommendations for more information.