Utilization of Aspen Trees as Ruminant Feed Component

When traditional roughages are in short supply or high in price, other fibrous feed sources for ruminants should be considered if available at a competitive price. One such fibrous material shown to have potential as a ruminant feed is the aspen tree (Populus tremuloids Michx.) harvested in its entire form to include bark, leaves and trunk. The aspen tree is the most widespread tree species in North America and the least utilized. Estimates exceed 6 million acres of mature trees in an area which would include the Black Hills (58,000 acres), the Great Lakes region and the Rock Mountain region. Since the tree responds to harvest by thirtyfold reproduction from the remaining stump and root, it becomes a highly renewable source of fiber. Previously, when aspen wood was properly supplemented to correct nutrient deficiencies such as protein, the final mixed ration was a satisfactory replacement for 80% alfalfa in growing rations for cattle (A.S. Series 76-19). The objective of this experiment was to further explore the use of aspen as the roughage portion of both growing and finishing rations. An attempt was also made to determine if chicken manure could partially replace soybean meal as a protein supplement in a ration having aspen as a major component.