Single-cut red clover combined with late timothy may be valuable in short-term rotations

Late-maturing cultivars of red clover (Trifolium pratense L.) and timothy (Phleum pratense L.) may be grown in short-term rotations with other crops and harvested for hay and silage. Harvesting forage in mid-summer is often advantageous for field curing, but the quality of mature forage may be low. We studied how harvests at different developmental stages affected yield, composition of herbage, and species persistence. The late-maturing single-cut red clover cultivar Altaswede and late timothy cultivar Farol were grown alone and in combination with and without applied N. Total forage, and red clover and timothy dry matter yields, increased between the first (27 June) and third (11 July) dates of harvest. Timothy grown alone or combined with red clover and fertilized with N produced greater forage yields than red clover alone or red clover + timothy without applied N. The in vitro digestibility of dry matter declined from 670 to 625 g kg−1 and crude protein from 134 to 109 g kg−1 between 27 June and 11 July. Water soluble carbohydrates in forage were low (36–66 g kg−1) in cuts 1 and 2. Macronutrient and micronutrient concentrations were generally highest at the first date of harvest on 27 June. Nutrient concentrations in cut 2 were similar for the three harvest schedules. We conclude that growing late-maturing single-cut red clover combined with late timothy produced high yields with good nutritional quality even at advanced stages of maturity. Single-cut red clover persisted for the first production year making this combination suited for short-term rotations that involve late harvesting of the primary growth. Key words: Red clover, Trifolium pratense, timothy, Phleum pratense, composition