Annual medics and berseem clover as emergency forages

Severe winter-kill of alfalfa (Medicago sativa L.) in some years prompts the need for emergency forages in northern locations. Three annual medic species-barrel medic (M. truncatula Gaertn. cv. Mogul), burr medic (M. polymorpha L. cv. Santiago), and snail medic [M. scutellata (L.) Mill. cv. Sava]-and berseem clover (Trifolium alexandrinum L. cv. Bigbee) and 'Nitro' alfalfa were seeded in early spring at East Lansing and the Kellog Biological Stations (KBS in Michigan in 1994 and 1995. Forage mass was measured at first harvest 60 d after planting and at second harvest 30 d later. Forage mass of annual medics at first harvest ranged from 0.8 to 3.6 Mg ha^-1 across locations and years. Berseem clover produced an average forage mass of 2.2 Mg ha^-1 at first harvest, which was similar to alfalfa. Crude protein (CP) concentration of annual medics, berseem, and alfalfa ranged from 111 to 210, 178 to 223, and 170 to 218 g kg^-1, respectively, at first harvest. Regrowth of annual medics (except Mogul) was less than alfalfa or berseem clover, however, the regrowth of Mogul was decumbent and not suitable as hay. Average forage mass and CP concentration of berseem at second harvest was 1.8 Mg ha^-1 and 191 g kg^-1, respectively, which was similar to alfalfa. Our results indicate that both annual medics and berseem clover can be used as emergency forages in northern locations; however, annual medics have the potential for only one harvest, whereas berseem can be harvested twice during the growing season.