Yellow sweetclover, subclover, white clover, and black medic formed an intermediate group for relative biomass production although performance of snail medic was similar to several species in the group.
Although no visible flowering occurred after any sowing time, black medic showed medium freezing resistance after all sowing times.
Also, the tested cultivars of crimson clover, yellow sweetclover, and black medic generally showed good freezing resistance, while subclover, barrel medic, and snail medic showed poor freezing resistance.
Plots in which only black medic had been seeded were not cultivated; this was the only treatment at soy-bean V5 stage with substantial cover crop establishment.
Average live cover crop after 1990 soy-bean harvest was not different whether cover crops were planted at SP or at soy-bean V1 stage (9% vs 10% live cover, [ILLUSTRATION OMITTED]); in 1991 black medic and hairy vetch live cover crop after soybean harvest was greater when seeded at soybean V1 stage rather than at SP.
Black medic density was 143 plants vs 54 plants/[m.
The difference between crimson clover and black medic was not significant, however.
In conclusion, the best frost resistance was shown by the hairy vetches, especially Hungvillosa, yellow sweetclover, crimson clover, and black medic, in that order.
Subclover and crimson clover and black medic in 1995-1996 also showed better ability for ground coverage and biomass accumulation than white clover.
Only some individual plants of black medic were still alive at Landvik and Jaeren.
Table 2 shows that all species survived at [Angstrom]s; however, black medic did rather poorly.