The Uses of Nitrogen for Wheat

Necessity

• Nitrogen serves as one of the principal elements for sustaining plant life. In nature, bacteria converts nitrogen from organic matter into a usable form that plants can absorb as food. While different crops or forms of vegetation require varying amounts of nitrogen, wheat seems to suffer a particular vulnerability to low levels of nitrogen in the soil. Wheat starved for nitrogen will display poor growth and yellowed leaves. As the leaves die, the plant loses the ability to yield usable wheat, posing a potential disaster for growers.

Benefits

• Wheat struggling to survive on limited nitrogen will use whatever nitrogen is available to grow new leaves instead of synthesizing protein. Mississippi State University notes that this tendency results in smaller heads, yielding less usable wheat grain. Nitrogen supplementation can increase both the protein levels and the yield of a wheat crop, with each pound of nitrogen fertilizer helping to support up to one bushel of wheat grain.

Application

• Nitrogen added to wheat during spring seeding generally works well except in very dry climates, which may respond better to a fall nitrogen treatment. Growers often drill the nitrogen into the ground right along with the seed for best results, or they may add a band or disc of nitrogen to the soil before the seeding takes place, a process known as banding. Another less effective method involves "broadcasting," or widely distributing nitrogen-based fertilizer onto the soil surface. In some cases growers may even spray liquid nitrogen onto the wheat crop, a method called foliar nitrogen application.

Considerations

• How well a wheat crop responds to nitrogen-based fertilizer may depend on a variety of external factors. Some of the nitrogen may escape into the atmosphere in the form of gaseous ammonia instead of remaining in the soil, an effect the Government of Alberta calls volatilization. Wheat seeded later in the growing season may have less time to use the nitrogen to its full effect. insufficient soil moisture can limit the effect of nitrogen on wheat while at the other extreme, flooded soil containing large amounts of nitrogen can damage or even kill the crop.