Nutritional quality and yield of seedling alfalfa established with a barley companion crop and weeds》.pdfVIP

Animal Feed Science and Technology 103 (2003) 163–169 Short communication Nutritional quality and yield of seedling alfalfa established with a barley companion crop and weeds ∗ M.S. Zaman , J.R. Moyer, A.L. Boswall, Z. Mir Agriculture and Agri-Food Canada, Lethbridge Research Center, P.O. Box 3000, Lethbridge, Alta., Canada T1J 4B1 Received 7 December 2001; received in revised form 18 October 2002; accepted 18 October 2002 Abstract Alfalfa (Medicago sativa L.) was established with barley (Hordeum vulgare L.) and weeds to determine the effect of weed management treatments on yield and nutritional quality of alfalfa and companion crop and weeds. Alfalfa + barley and alfalfa + wild oat (Avena fatua L.) had much higher yields in August of the first year than alfalfa alone. Total yields for the first three harvests were similar for alfalfa established weed free, with broad leaf weeds, wild oat or green foxtail (Setaria viridis L.). Protein contents in forage from the August harvest were 228, 196, 117 and 181 g/kg dry matter (DM) in weed free alfalfa, alfalfa plus broadleaf weeds, alfalfa plus wild oat, and alfalfa plus green foxtail, respectively. Alfalfa + barley had higher total in vitro gas production than pure alfalfa, which is correlated with the digestibility of the forage. Total in vitro gas production indicated that alfalfa +barley +weeds had slightly lower digestibility than weed free alfalfa +barley. However, alfalfa with a high percentage of redroot pigweed (Amaranthus retroflexus L.), wild oat or green foxtail had similar or higher in vitro gas production than pure alfalfa. The results from this experiment support a previous economic study that indicated herbicide application for weed control in seedli