Small grain crops have been a popular risk management tool in many mid-Atlantic states as both a cover crop and a source of forage early in the growing season. The challenge with these crops is that their growth, yield and nutrient content are greatly influenced by weather. Timing of moisture and temperature after planting has a strong influence on early growth and development of a stand to overwinter successfully. Winter and spring moisture along with the onset of warm weather in the spring greatly influence the rate of growth of the crop and its nutrient content and yield. These conditions can mean the difference between boom and bust in terms of yields and nutrient content as shown below. In addition to moisture, stage of maturity at harvest has a large impact on energy and protein content. Small grains mature very rapidly under warm growing conditions. For optimum dry matter and energy yield, barley and triticale should be harvested at the “soft dough” stage of maturity when the seed heads have filled but are still soft. Cutting too early results in higher fiber, lower starch and less energy.
The table below shows two samples of barley silage harvested in 2009 and 2011. The 2009 sample shown was the result of poor growing conditions in the fall and spring. It also was harvested too early, before the seed heads had accumulated optimal amounts of starch. The 2011 crop was the result of adequate moisture and temperatures after planting which enabled establishment of a relatively good stand of small grains. Abundant rainfall of over 7 inches in March and April and relatively warm average temperatures of 56oF in April resulted in excellent barley growth and development. This forage was harvested at an optimal stage of maturity and wilted to the recommended level of dry matter.
What impact does small grain quality have on dairy rations? When corn prices exceed $8.00/bushel, dairy producers need to consider all measures possible to manage energy costs. Rations were formulated for a herd of Holsteins producing 85 lb. of milk with 3.8% fat using analysis for each of these forages as the basis of the rations with all other ingredients remaining the same. The 2011 barley silage resulted in a ration that used only a 1–2 lb. more barley silage dry matter and 3 lb. less ground corn to provide similar levels of NE and protein. With corn priced at $9.00/bushel, this resulted in a savings of $.48/cow per day in purchased feed cost. In addition to cost, the higher quality silage enabled greater quantities of forage to be included in the ration which should encourage higher fat test and better digestive health.
Given the high price of corn and the excellent growing season we have had, small grain forages might be a more valuable asset than expected. Develop a protocol for nutrient analysis, which includes representative sampling and testing on a frequent basis (at least monthly), to assure that the nutrient value of small grain silages are fully realized.