
Use of a mechanical roller crimper as an alternative kill method for cover crop
D. L. Ashford1 and D. W. Reeves2
Abstract
Cover crops have long been recognized as a beneficial component of many cropping systems; however, their use is still not commonplace. Usage may be increased by identifying more cost-effective and environment-friendly techniques for cover-crop management.
This study was conducted to determine the effectiveness of using a mechanical roller-crimper as an alternative method for killing cover crops. The study location was in east-central Alabama, using a split-split plot experimental design with four replications and 3 site-years during 1999-2000.
Rye, wheat and black oat were evaluated in terms of ease of kill and optimum time of kill using a roller-crimper, no herbicides (paraquat and glyphosate) at their labeled rate, and two reduced chemical (half label rate) combinations of the same chemicals with the roller-crimper. Four Feekes' scale growth stages were used to determine optimum time of kill; 8.0 (flag leaf), 10.51 (anthesis), 10.54 (early milk) and 11.2 (soft dough).
Plant growth stage was the main determining factor for effectiveness of the roller-crimper for killing the cover crops. At the flag leaf stage, the roller-crimper provided only 19% kill across all covers over the 3 site-years. After plants reached anthesis, the roller-crimper with half-rate herbicide combinations equaled the effectiveness of herbicides alone at their label rate, averaging 94% kill. By the soft dough growth stage, all kill methods were equally effective due to accelerating plant senescence (95% mean kill across kill methods).
Use of the roller-crimper alone after anthesis can decrease costs by as much as $26.28 per ha, while providing a kill rate equivalent to that of herbicide treatment alone.
Source
American Journal of Alternative Agriculture (2003) 18: 37-45
Author Locations and Affiliations
(1) USDA-NRCS, Clinton, NC 28328
(2) USDA-ARS National Soil Dynamics Laboratory, 411 South Donahue Drive, Auburn, AL 36832
Posted April 2010
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