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I’m interested in no-till weed suppression. Where can I get more information about roller-crimpers?

F.W.KentuckyAnswer: The mechanical roller-crimper is a tool that “rolls down” and “crimps” the stalks of cover crops for no-till weed suppression. Mechanical suppression of cover crops for no-till production can be accomplished through various kinds of mow-down and rolling/slicing/crimping techniques. These non-chemical methods of killing cover crops are appealing as an alternative to chemical-kill methods using synthetic herbicides. The roller-crimper is a round drum with protruding blunt metal blades arranged in horizontal, angled, or spiral patterns. Roller-crimpers are most commonly rear-mounted and pulled behind a tractor or draft animals, but they can also be front-mounted and designed to fit most any type of “vehicle.” This includes 4-wheelers. In fact, my colleague and I easily designed and built one that is pulled by hand. The idea is to bend the cover crop plant over and crimp the stem every 6 to 7 inches along its length. Any tool that does this has a good chance of being effective.When the roller-crimper is pulled through a high biomass cover crop?such as wheat, rye, oats or oilseed radish?the cover crop is flattened and “crimped” by the heavy drum with metal strips. The purpose of the metal strips is to crimp or crush the stems of the cover crop rather than cutting or chopping the stems; this simultaneously prevents re-sprouting and slows down decomposition of the no-till mulch. No-till crops are seeded or transplanted in the same direction of the flattened and crimped cover crop, which slowly senesces and dies out over the course of several weeks, leaving high residue no-till mulch. The drums are designed to be filled with water for added weight. The amount of water added varies depending on the size of the roller as well as the field conditions it will be used on. In other words, different field conditions will require different amounts of added weight. The timing of the roller-crimper field operation is critical to gain effective kill of the cover crop. Cereal-based cover crops should rolled at the “anthesis” (flowering) stage of growth or later?in the milk or soft dough stages of growth, a period which corresponds to the mid-spring planting season shortly after the last frost-free day. Growers can refer to charts published by the Extension Service on the Feekes or Zadoks scale of crop growth to gain a clear understanding when anthesis, milk, and soft dough stages occurs (1?2). The Rodale Institute, Kutztown, PA, is spearheading research on roller-crimper equipment designs and on-farm trials using roll-down, no-till production systems. The Rodale Institute has published several noteworthy articles and updates on their roller-crimper research project, including photos which are all located on their web site: This site also contains AutoCAD drawings of their design. Below you will also find the contact information for Buckeye Tractor Company, located in Ohio. Buckeye Tractor Company manufactured the 3-point hitch for front-mounting the roller-crimper for the Rodale Institute. Thus far I am aware of two equipment manufacturers in the United States that supply roller-crimpers: I & J Mfg. in Pennsylvania, and Bigham Brothers Mfg. Co. in Texas (3-5). These roller-crimpers can be custom-made according to any width a farmer might need, based on tractor, 4-wheeler, or draft animal team size, and field layout. According to I & J Mfg., their 10.5 foot roller for a tractor mount weighs 1,600 lbs. empty and 2,400 lbs filled with water. In addition, farmers are using various brands of stalk choppers, roller harrows, cultipackers, bed rollers, and land rollers, either factory-made or custom modified, to accomplish the same function of rolling down cover crops for no-till production.References:

  1. Wheat Growth Stages and Associated Management (e.g., Feekes scale) Ohio State University Extension
  2. Growth and Development Guide for Spring Wheat (e.g., Zadoks scale) University of Minnesota Extension
  3. Buckeye Tractor Co. P.O. Box 97, 11313 Slabtown Road Columbus Grove, Ohio 45830 419-659-2162 800-526-6791Toll-Free 419-659-2082 Fax
  4. I & J Manufacturing 5302 Amish Road Gap, PA 17527 717-442-9451 717-442-8305 Fax
  5. Bigham Brothers, Inc. P.O. Box 3338 Lubbock, Texas 79452 806-745-0384 800-692-4449 Toll-Free 806-745-1082 Fax