Be SMART about moisture stress

When a farmer plants a crop the end-result depends on countless variables. Moisture is the leader of the pack when it comes to erratic factors affecting seed germination, crop growth, and final yield and protein results. With moisture as an unpredictable opponent, it’s important for farmers to arm themselves with the best tools out there – starting with the right nitrogen (N) fertilizer.

ESN SMART NITROGEN® helps protect the N as well as the seed.  Too much moisture can result in loss of N, while too little moisture can result in seed damage when seed placing N fertilizer.

“Many areas of the prairies don’t have sufficient moisture available for crops throughout the growing season,” explains Ross McKenzie, PhD, P. Ag, a retired agronomy research scientist, previously with Alberta Agriculture. “When there’s not enough soil moisture to meet the requirements of the crop, it leads to moisture stress conditions.  In most years on the prairies, there has been some level of moisture stress during the growing season.”

Having enough N is crucial for achieving optimal yield and high protein content – especially when a crop is under stressful conditions and getting too much or too little moisture. If the N fertilizer used is in the form of conventional urea, high moisture conditions can lead to losses of N; under dry conditions – the germinating seed may be damaged by N fertilizer.

Using ESN – the only controlled-release N fertilizer available – protects the seeds and the fertilizer during moisture stress conditions. “ESN works well when conditions are dry and when they’re wet because it regulates N release based on soil moisture conditions and the seed’s requirements,” explains McKenzie.

“Placing ESN with the seed instead of straight urea means the seed will be much safer. The polymer-coating encapsulating the urea minimizes the toxicity effect of too much seed-placed fertilizer and minimizes the competition between the seed and fertilizer for moisture,” says McKenzie.

Because the urea in ESN releases over time, McKenzie suggests that farmers using 100% ESN can typically apply at least three times the amount of ESN as they could straight urea.

“Water has to move through the porous polymer coating of ESN to dissolve the urea, meaning that when conditions are drier; this won’t happen as quickly, minimizing the risk of ammonia toxicity. If the soil dries out, the release will slow down and then once it rains, the release will speed up again,” explains McKenzie.

The release is timed for when the crops need N the most. “If it’s quite dry, the crops move into a holding pattern of sorts, where they tend to slow down growth and don’t need as much N. ESN helps to conserve the N so it doesn’t get lost,” comments McKenzie.

“ESN’s controlled release gives an advantage; ensuring N is available when the plant shifts from vegetative to reproductive growth, combating some of the negative effects of moisture stress.”

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