ORGANIC MULCH AND NITROGEN AFFECT SPRING AND FALL COLLARD YIELDS

Fall and spring collards (Brassica oleracea L. Acephala Group) were gr own under one of three mulches (black plastic, ground newspaper, wood chips) and in a bare soil control, Mulch treatments were arranged in a factorial design with five rates of N fertilizer: 0, 67, 134, 201, or 268 kg N/ha, All fertilizer was preplant-incorporated into the bed be fore applying mulches and transplanting collards, Season did not affec t collard yield, and there was no significant season x N rate interact ion, Collard yields increased with increasing rates of N, with a maxim um yield at 163 kg N/ha, Mulch type significantly affected collard yie ld, with fall collard yields highest under bare ground or wood chip mu lches and spring yields highest under black plastic mulch, Collards pr oduced under newspaper mulch produced the lowest yields in the fall an d yields equal to bare soil and wood chips in the spring, Collards pro duced under newspaper mulch had less tissue N at harvest than those of any of the other treatments in both seasons, Collards produced on bla ck plastic produced the lowest plant populations in both seasons, Wood chips and newspaper offer some appeal as low-input, small-scale mulch es, but additional research to explore fertility management is necessa ry.