The heat and drought have caused cattle producers to look for methods of adjusting to local conditions. Many who don't want the expense of additional feeds are considering early weaning and selling replacement heifers. However, an alternative may be ammonia treatment of low quality forages, according to UNL specialists Tom Holman and Aaron Berger and Gary Hergert in Scottsbluff.
For wheat producers who choose to bale their straw, this provides an opportunity for additional income. But there are drawbacks to removing straw. Many producers leave wheat residue to enhance soil moisture storage for future crops. And some nutrients are also removed in the straw, which can affect future crops.
Irrigated wheat produces considerably more straw, and a portion can be removed and still leave some residue. Straw production rates can be predicted fairly accurately if you know grain yield. The Harvest Index--ratio of grain to total dry matter--for most semi-dwarf wheat varieties planted in western Nebraska is about 0.3. A 40-bushel wheat crop will produce about, 5600 pounds, or 2.3 tons, of straw. An 80-bushel wheat crop will produce over 5 tons of straw per acre.
Straw is an ideal source of forage to ammoniate for beef cows, Berger says. With wheat harvest so early in many areas, some are considering planting hay millets behind straw harvest to produce another "hay" crop to increase income. Crop production budgets for millet and sorghum-sudan crosses following irrigated wheat are currently being developed by Jessica Johnson, Extension Educator in ag economics at the Panhandle Research and Extension Center.
Treatment of low-quality crop residues with anhydrous ammonia improves their digestibility. Moisture content of the forage is important. Ideally, best results of ammoniation occur when the forage is greater than 10% moisture. Also, ammoniation of forages is successful when the air temperature is more than 80 degrees. Adequate heat has not been a problem of late across most of the High Plains, but waiting until fall is not advised.
Ammoniation is accomplished by covering the straw pile with plastic and applying ammonia to the covered straw. Procedures and how to estimate the amount of anhydrous to apply are listed in UNL Extension Publication EC89-265, which can be found at http://digitalcommons.unl.edu/
Presently, anhydrous is selling for $820 per ton, wheat straw is averaging $85 per ton, labor is estimated at $12 per hour and alfalfa hay is estimated at $180 per ton at 18% crude protein, 15% moisture and 56% total digestible nutrients (59 cents per pound of protein and 19 cents per pound of TDN).
Assuming that 6-8 mill black plastic sheets are selling for 7 cents per square foot, a 40 time 100 sheets would cost $280 and plastic pipe would cost $35. Following are some estimates costs to ammoniate a ton of wheat straw:
- Equipment (plastic and pipe): $9.33
- Anhydrous ammonia: $24.60
- Labor: 0.13 cents
- Bale wheat straw: $15.82
- Total: $49.88/ton
Ethanol byproducts or other feeds such as beet pulp and soy hulls can be fed along with wheat straw to meet cow nutrition needs. By evaluating and comparing feed options, producers can develop the most cost effective ration to meet livestock needs.