Hansen, M. J., Owens, V. N., Beck, D. and Sexton, P. 2013. Suitability of cover crop monocultures for late-season forage in South Dakota. Can. J. Plant Sci. 93: 589-597. Cover crops provide many agronomic benefits and can produce large amounts of forage that is suitable for grazing. The objectives of this study were to determine (1) suitable cover crop forages based on yield and nutrient values; and (2) changes in feed value and yield of these crops through the late fall. Five cover crop monocultures consisting of lentil (Lens culinaris Medikus), cowpea (Vigna unguiculata L.), foxtail millet (Setaria italica L.), oats (Avena sativa L.), forage radish (Raphanus sativus L.), and a mixture of these crops were planted after winter wheat (Triticum aestivum L.) harvest in 2010 and 2011 in central and southeastern South Dakota. Forage data were collected on approximately Oct. 01, Nov. 01, and Dec. 01 each year. Yields increased after the first harvest date at both sites, both years. Oats, radish, and the cover crop mixture all yielded >4000 kg of dry matter per hectare on the second harvest date in 2011 in central South Dakota and radish and oats yielded >4000 kg ha^-1 in southeastern South Dakota on the second and third harvest dates, respectively. Forage quality tended to decrease after each harvest date. Radish in central South Dakota in 2010 had the highest protein values for the study (194-313 g kg^-1) whereas oats in southeastern South Dakota had the lowest protein concentrations (63-108 g kg^-1), both years. All cover crops except cowpea were viable forages through the late fall when they had good establishment with the potential need for protein supplementation with oats, foxtail millet, and the cover crop mixture, depending on animal requirements.