October 26, 2007

Fall application of anhydrous ammonia is not recommended on coarse textured soils where leaching potential is high.

For more information . . . see Nutrient Management for Agronomic Crops in Nebraska, a 176-page book available on-line or for $12 from Extension offices.

Nitrogen in knife applications of anhydrous ammonia and liquid swine manure is more likely retained in the soil when soil temperatures are low. Nitrification slows as soil temperature drops.

The standard recommendation is to delay anhydrous application until soil temperatures drop to 50°F or 55°F if a nitrification inhibitor such as NServe or DCD is used.

The problem is that when the soil temperatures are low, the anhydrous ammonia temperature is low and the pressure to move the anhydrous ammonia out of the tank may be too low to apply the rates that the farmer wants. Swine slurries and effluent would not have this problem since they are pumped out of the honey wagon.

Charles Shapiro
Soil Scientist - Crop Nutrition
Haskell Agriculture Laboratory, Concord