Alfalfa and sainfoin were sown in 1978, 1979, and 1980 on irrigated land at the Lethbridge Research Station. The forages were established using herbicides for weed control, no weed control, or a barley companion crop. Weed control treatments were applied only during the establishment year (year 1). Alfalfa yields, averaged from the three seedings, were 360 and 200 g/m2 greater during year 1 and year 2, respectively, when diclofop plus 2,4-DB was applied than when the companion crop was grown and no weed control was used. Weed yields were greater in years 2 and 3 where alfalfa was established in competition with weeds or companion crops than where weeds were controlled. Alfalfa yields were similar for all treatments in years 3 and 4. Year 1 treatments in sainfoin produced yield differences similar to those described for alfalfa; however, sainfoin yields tended to be smaller and weed yields larger. Year 1 and year 2 forages with high weed contents have acceptable nutrient composition but may not be saleable as hay or silage or to the dehydration industry. The seeding of pure stands of alfalfa on irrigated land using herbicides for weed control produced sufficient high quality forage, in year 1, to make this practice a viable alternative to seeding with a companion crop.Key words: Alfalfa, sainfoin, 2,4-DB, diclofop, MCPB, fiber, protein
Effect of weed control methods on weed infestation of durum wheat (Triticum durum Desf.) and common wheat (T. aestivum L.) crops