Resist Temptation to Do Business as Usual in Dry Fall

Systems don't work the same in extremely dry soil.

Published on: Nov 17, 2010
Earlier we noted that Jeff Phillips was advising farmers who asked him to wait on applying anhydrous ammonia this fall. Part of his concern was based on soil temperature, and soil temperatures certainly warmed up again last week. More of it was based upon whether the anhydrous ammonia application rig could do a good job sealing the product in the soil given super-dry conditions.

Phillips, Extension ag educator in Tippecanoe County, hasn't changed his mind. He notes that several fare applying anhydrous ammonia anyway, dry or not, recommendation ro not, but he still believes the best economic thing to do is wait for a time when soil conditions are more favorable to make the application.

"I was out last week and checked a couple fields where the farmer had just applied anhydrous ammonia with an injection rig," he notes. "You could still smell ammonia in the field four hours after he finished the application. That's telling me that we're not getting the sealing that we need to hold the product in the ground."

Research has shown that fall-applications of anhydrous ammonia are the least efficient of all application methods anyway. There will typically be some losses over winter, although it varies year to year. Adding a nitrification inhibitor, which would be N-Serve for anhydrous applications, helps cut loss potential over winter, and is definitely recommended if you are going to apply anhydrous in the fall, experts say.

The other problem farmers who've just bought new vertical tillage tools are having is deciding whether to run them or not. At least one farmer says he's still getting some mixing with soil, and is not just cutting stalks on top. However, he knows that he isn't getting the mixing he would like if soil was in a more typical condition and not so dry.

Having enough power to pull the tool through dry soil is not a huge issue since vertical tillage tools are designed to run very shallow, typically about two inches deep, and very fast, often up to 9 miles per hour. The question is whether you're getting the mixing you want and whether the trailing tool, often a rolling basket, is leaving the surface smooth and ready to plant or drill into next spring.

The theory behind vertical tillage tools is that when run in the fall, particularly on heavy corn residue, shallow incorporation of residue begins the breakdown process of stalks. That assumes, however, that there is adequate moisture available to begin the breakdown process. That remains a question mark so far this fall.