The final N recommendation is an average optimal rate. Your final N rate decision may be plus or minus 20 pounds N per acre from that value depending on individual field situations. The value assumes an optimal N application and timing strategy. If these strategies are not optimal, a greater N rate maybe needed. Suboptimal N application strategies include to early N application the fall prior to seeding, surface urea/UAN application or lightly incorporated urea/UAN, or shallow ammonia application. Fields that are first year sunflower, or sunflower more then 4 years after a deep rooted crop including sunflower may have have deep N, and a minimal N preplant application followed by side-dress application at V5-V8 is recommended.

Nitrogen recommendation in this app is based on an economic production function that takes into account the yield response of corn to added N, less the cost of the N.

High clay soils are subject to N loss due to denitrification in wet years. If spring rainfall is normal and the soil is muddy for less than 10 days, the preplant N recommendation should be sufficient for high yield. If rains result in muddy conditions for more than 10 days, supplemental N as sidedress is strongly recommended. Estimate 1.5% nitrate-N loss per muddy day. A better recommendation is to utilize the high clay soil with yield potential greater than 160 bushels per acre active-optical sensor algorithm to direct variable-rate sidedress rates. The active-optical sensor algorithm will require the grower to establish an N-rich strip in the soil category within a variety for its use.

Nitrogen recommendation in this app is based on an economic production function that takes into account the yield response of spring wheat/durum to added N, less the cost of the N.

The final Nitrogen recommendation is the average optimal rate. Growers may choose to apply up to 30 lb N/acre more or less than the calculated N rates due to protein traits of a variety, special soil conditions such as susceptibility to spring denitrification, application techniques that may not be most efficient or historical experiences from the field or part of a field that may influence N uptake and efficiency. For wheat after small grains, we assume about 2,000 lb/acre of straw residue. For every 2,000 lb/acre straw greater than this, add 30 lb N/acre.

This recommendation value is only for 2-row malting barley.

Nitrogen recommendation in this app is based on an economic production function that takes into account the yield response of barley to added N, less the cost of the N.

The final Nitrogen recommendation is the average optimal rate. Growers may choose to apply up to 15 lb N/acre more or less than the calculated N rates due to protein traits of a variety, special soil conditions such as susceptibility to spring denitrification, application techniques that may not be most efficient or historical experiences from the field or part of a field that may influence N uptake and efficiency.