Performance of Different Roller Designs in Terminating Rye Cover Crop and Reducing Vibration

Rollers may provide a viable alternative to herbicides for terminating cover crops; however, excessive vibrationgenerated by rollers and transferred to tractors hinders the adoption of this technology in the United States. To avoid excessivevibration, producers must limit their operational speed, which increases time and cost of rolling. The effect of speed on covercrop termination rate and vibration level was tested on several roller designs. Two field experiments were conducted withdifferent roller designs to terminate a cover crop of rye (Secale cereale L.). In the first experiment, three single-section rollerdesigns (long straight bars, curved blunt bars, and a smooth roller with an oscillating crimping bar) were tested at 1.6, 4.8,and 8 km/h operating speeds. In the second experiment, two triple-section commercial width rollers, one with long straightbars and the other, a smooth roller with an oscillating crimping bar, were tested at speeds 3.2 and 6.4 km/h. Data from thefirst experiment showed that all three roller designs terminated at levels greater than 90% with the highest termination rateproduced by the smooth roller with crimping bar (93.4%). Three weeks after rolling, termination rates varied from 88.3% to94.0% for all designs and speed ranges, all of which were sufficient mortality rates for rye before planting a cash crop withoutneed to use herbicide. Reduced vibration levels measured on the tractors frame were generated by the smooth roller withoscillating crimping bar with the highest vibration levels being generated by the roller with the straight bars. In the secondexperiment, three weeks after rolling significantly higher rye termination rates resulted from the roller with long straight bars(96%) in comparison with the smooth roller (94%). Despite these differences, both rollers effectively terminated rye priorto planting without use of herbicides. The smooth roller with crimping bar transferred significantly lower vibration levels tothe tractors frame than long straight bar roller at both speeds but vibration levels exceeded acceptable health and comfortlevels.