405 No-till Vegetable Production in the Sand Hill Region of North Carolina
An experiment was established to determine the effect of different winter cover crops residues on yields of no-till pumpkins, yellow summer squash, and sweet corn. Residue treatments of fallow, triticale, crimson clover, little barley, and crimson clover + little barley were fall established and killed before spring no-till planting in 1998 and 1999. All summer vegetables received recommended fertilizer rates and labeled pesticides. Spring cover crop growth and biomass measurements ranged from 1873 to 6362 kg/ha. No-till sweet corn yields among the various cover residue treatments were greater where crimson clover and crimson clover + little barley (mixture) were used as residue in 1999, but not significantly different in 1998. No-till pumpkins showed the beneficial affect cover crop residue had on vegetable yields when dry conditions exist. Triticale and crimson clover + little barley (mixture) residues reduced soil water evaporation and produced more numbers of fruit per hectare (5049 and 5214, respectively) and greater weights of fruit (20.8 and 20.9 Mg/ha) than the other residue treatments (3725 to 4221 fruit/ha and 11.8 to 16.1 Mg/ha, respectively). No-till summer squash harvest showed steady increases in yield through time by all treatments with crimson clover residue treatment with the greatest squash yields and triticale and little barley residue treatments with the lowest squash yields. We found that sweet corn and squash yields were greater where legume cover residues were used compared to grass cover residues, whereas, pumpkin yields were higher where the greatest quantity of mulch was present at harvest (grass residues).