Farm Talk

July 3, 2012

Using ammonia when quality forage is limited


Parsons, Kansas — Perhaps “making a silk purse from a sow’s ear” may be a little strong when comparing the process of ammoniating low quality roughages such as wheat straw and fescue hay cut after seed harvest.

However, the practice of adding anhydrous ammonia at the rate of around 2.5 percent of the actual weight of the hay is research proven according to Eldon Cole, a livestock specialist with University of Missouri Extension.

“The process is used when quality forage supplies are limited, like during dry period we are having now,” said Cole.

The ammonization process does several favorable things to the low quality forage. For example, it improves digestibility, roughly doubles the crude protein content, improves animal intake and acceptance, prevents mold formation in the bale, and appears to reduce ergovaline toxicity in fescue hay.

The anhydrous is added to a large bale pile that is covered by six mil thickness, black polyethylene. The 40 by 100 feet of plastic is covered around the edges of the bale pile with dirt or limestone to seal the pile and keep it airtight.

The stacking and covering should take place soon after baling is completed. Moisture in the forage helps distribute the anhydrous throughout the pile. The ideal moisture level is 15 to 18 percent. In warm weather, the treatment will make the hay ready to feed in about three weeks according to Cole.

“Those who ammoniate forage, usually use large round bales with 90 to 100 bales under the plastic. Bale stacking can be done during the day. The covering is best done late evening when there is less wind,” said Cole.

Cole says bale stacks are usually oriented north and south, away from trees and where wind currents are less. Wind is a problem if the plastic flaps and tears. The treated bales need to remain covered until a day or so before feeding.

As good as ammoniaiton is, there are some drawbacks. For example, there is an added cost, lack of an anhydrous ammonia source in many non-row crop areas, the process requires time and labor and bales and anhydrous need to be weighed to know the amount of anhydrous to apply.

Also, if too much anhydrous is applied or the forage quality is above average and the treated hay is the only feed cattle consume, a nervous, excitable condition can occur that could result in cattle deaths. This condition not only affects older animals, it can be passed through the milk to nursing calves.

For additional information on the ammoniation of low quality hay or straw, contact any of these MU Extension agronomy specialists in southwest Missouri: Tim Schnakenberg in Stone County, (417) 357-6812; John Hobbs in McDonald County, (417) 223-4775 or Brie Menjoulet in Hickory County, (417) 745-6767 or Eldon Cole at (417) 466-3102.£