Ensiling Characteristics of Alfalfa Leaves and Stems

摘要

The separate harvesting of alfalfa leaves and stems would provide farmers more flexibility in the harvesting and utilization of alfalfa, but a key issue is storage. In three trials, unwilted alfalfa leaves were ensiled alone or with cell wall degrading enzymes, formic acid or lactic acid bacterial inoculant. Alfalfa stems wilted to 350 g DM/kg were ensiled with the same four treatments. In the two trials where the leaves were above 230 g DM/kg, the leaves ensiled successfully without any additives. Leaves ensiled at 168 g DM/kg eventually underwent a clostridial fermentation with elevated levels of butyric acid and ammonia, regardless of the treatments used. Formic acid could be used to guarantee a good fermentation, but more research is needed to ascertain the addition level as a function of the DM concentration of the leaves. The stems when wilted to approximately 350 g DM/kg ensiled well without additives. The enzyme and inoculant treatments affected fermentation as expected but were not necessary for good preservation by ensiling. Their value to the producer would depend on other factors not measured: improving DM recovery from storage and/or enhancing utilization by livestock or as a biomass feedstock.