Saturday, April 29, 2017
Nitrogen Loss in Saturated Soils
We sometime hear that lots of rain will leach our nitrogen fertilizer. My experience is that unless the soils are very sandy, most of the nitrogen loss will be from denitrification. In other words, the nitrate nitrogen is converted to unavailable forms. Losses will be much less on recently applied anhydrous ammonia than on fields where nitrate forms have been applied, or where early applied nitrogen has already nitrified. This article out of Mississippi puts some numbers to it. In warm weather we can lose up to 5% a day. Some testing might be in order when soil have dried out. When oxygen gets back into the system, There will be some renitification. Cultivation can encourage that, but it will not take the place of fertilizer entirely. You models such as Climate or Yield 360 can be useful too, but I do not trust them entirely.