Submitted to: Proceedings of Southern Weed Science Society
Publication Type: Abstract Only
Publication Acceptance Date: 1/24/2005
Publication Date: 1/24/2005
Citation: Price, A.J., Balkcom, K.S., Arriaga, F.J. 2005. Weed suppression provided by rye and clover in conservation-tillage cotton and corn. In: Proceedings of Southern Weed Science Society, January 24-26, 2005, Charlotte, North Carolina. 58:33.
Technical Abstract: Previous research has shown that a winter cover's planting date and termination date influences both quality and quantity of residue production, and subsequent weed suppression. Therefore, a field study was conducted at the E.V. Smith and Tennessee Valley Research and Extension Centers to determine optimum dates for planting and terminating winter cover crops to maximize biomass production, summer annual weed suppression, and cash crop yields. Rye and crimson clover were established with a no-till drill as winter covers, preceding conservation-tillage cotton and corn, respectively, at 2 and 4 wk prior to, 2 and 4 wk after, and on the historical average first frost. In the spring, winter covers were terminated at 4, 3, 2, and 1 wk prior to cash crop planting with glyphosate at 1.12 lb ai/ha. At E.V. Smith, rye planted 4 wk after first frost and terminated 4 wk before cotton planting produced the least biomass, 318 kg/ha, 27 times less than highest biomass treatment in which rye was planted 4 wk prior to first frost and terminated 1 wk prior to cotton planting. Correspondingly, weed biomass was 1,198 kg/ha in the treatment with the least rye biomass, 42 times greater compared to the treatment with the greatest rye biomass. Similar relationships were observed at the Tennessee Valley site. At E.V. Smith, clover planted 4 wk after the first frost and terminated 2 wk before corn planting produced the least biomass 406 kg/ha, nine times less than the highest biomass treatment in which clover was planted 2 wk prior to first frost and terminated 2 wk prior to corn planting. Weed biomass was 77 kg/ha in the treatment with the least clover biomass, eight times greater compared to the treatment with the greatest clover biomass. Again, similar relationships were observed at the Tennessee Valley site.