Municipal yard waste is an abundant natural resource in the areas of the south with hardwood trees. Composting often is accomplished at the waste facility, and they give the material away in most cases. Utilizing this resource in organic potting mixes for mulching and for increasing organic matter in the soil makes sense. Unfortunately trash, rocks and other debris contaminate what would be an excellent source of organic matter.
In the project, the grower modified an existing tractor-mounted concrete mixer to remove the contaminants from yard waste. He reasoned that a farmer with a reasonably efficient screening system would be able to utilize unscreened yard waste from a nearby facility. This would reduce the need to go farther from the farm to obtain and transport a higher quality yard waste. He found that the orbital action of a trommel type screener is more efficient than a vibrating screen method.
To determine the best cylinder shape and size it was necessary to first modify the cylinder that comes with the implement. This was done by cutting a series of rectangular openings around the circumference and securing rabbit-wire screen over these openings.
The modification of the stock cylinder was easy to accomplish. The next goal, to increase efficiency by screening more material per hour, is to determine how the screened material could be removed from under the screening cylinder to a container or trailer.