Fall Nitrogen - Anhydrous Ammonia
Throughout a large portion of central Illinois harvest has been or is nearing completion. Some farmers are even wrapping up fall tillage and are prepping equipment for fall anhydrous ammonia applications. Anhydrous Ammonia is a great source of nitrogen that can be applied both in the fall and spring. Soil temperatures have been dropping in recent weeks and are nearing the suggested application mark, but we aren't there yet. It is also a good idea to use a nitrification inhibitor to protect against nitrogen loss in the fall.
Here are some 4R Code of Practices from the IFCA that apply to fall/winter fertilization.
• For fall applied nitrogen, we will recommend waiting until maximum daily soil temperatures at the 4 inch level fall to 50° and temperatures are predicted to continue to decline.
• We will recommend the stabilization of fall applied nitrogen fertilizers with labeled nitrification inhibitors.
• We will not recommend the application of dry fertilizer on snow covered soils and will also discourage the application of a majority of a customer’s nutrient needs on bare, frozen soils. When such requests are made, we provide 4R based management alternatives with the exception of fall sown cereal grains, perennial and permanent pastures and hay land. “Snow Covered” means no soil in the field of application can be seen due to snow cover. “Frozen” means soil conditions are such that tillage or incorporation after application is not possible at the time of application and will not be possible prior to weather conditions that could be conducive to excessive runoff from the field.
Source: Illinois Fertilizer & Chemical Association (IFCA) "Keep It 4R Crop" http://www.keepit4rcrop.org/