Proceedings of the Sixty-first Annual Meeting of the Northeastern ...

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EFFECTIVENESS OF A ROLLER/CRIMPER FOR CONTROL OF WINTER ANNUAL
COVER CROPS. W. Curran, S. Mirsky, and M. Ryan, The Pennsylvania State Univ.,
University Park.
ABSTRACT
Cover crop roller/crimpers are increasing in popularity. In 2005, Penn State
University constructed a roller/crimper designed after a Rodale Institute prototype. Over
the last two years, several experiments have investigated the effectiveness of the
roller/crimper for control of winter annual cover crops. Most of the efforts at Penn State
have focused on cereal rye control as influenced by planting date in the fall and
termination date in the spring. In 2006, additional trials examined reduced rates of
herbicide in combination with the roller/crimper for control of both cereal rye (Secale
cereale) and hairy vetch (Vicia villosa). Glyphosate was examined in cereal rye and
2,4-D was used in the hairy vetch trial. A third experiment in 2006 examined the
effectiveness of the roller/crimper for control of winter rape (Brassica napus) alone and
in combination with glyphosate. In the rape experiment, two application timings based
on cover crop growth stage were examined. In all experiments, either Roundup Ready
corn or soybean was no-till planted shortly after rolling the cover crops and glyphosate
was used for in-season weed control.
The results of the cereal rye experiment showed that the roller treatment alone
only provided about 50% control of the cover crop. The rye was just beginning to head
and not yet susceptible to control with rolling alone. The combination of glyphosate
applied at either 0.093 lb ae/A (1/8X) or 0.1875 lb/A (1/4X) with rolling provided 85%
and 94% rye control, respectively 14 days after application. The reduced rates of
glyphosate alone provided 67 and 89% control. In the hairy vetch trial, rolling alone
provided about 75% control of the hairy vetch and the addition of 2,4-D LVE increased
control to over 90%. Again, the hairy vetch was just beginning to flower and not
completely susceptible to control from rolling alone. Hairy vetch is very susceptible to
2,4-D and application of 0.25 lb ae/A provided effective control regardless of the roller
treatment. Finally, rolling winter rape alone at either the early or mid flowering stages of
growth was not very effective for control and a full rate of glyphosate (0.75 lb/A) was
necessary to achieve greater than 85% control. Glyphosate applied at 0.375 lb/A
provided about 80% winter rape control.
The results of this research show that reduced rate herbicide programs combined
with roller/crimper technology can be more effective for control of certain cover crops
such as cereal rye than either tactic alone. For other cover crops such as hairy vetch
and winter rape, the roller/crimper is less effective for control and will require alternative
tactics or strategies for effective control prior to establishing a cash crop.
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