Waste Prevention and Reduction 

Wasteshed programs for a two percent recovery rate credit
Grasscycling

Oregon Administrative Rule 340-090-0045(3)(b)(A): a program to encourage leaving grass clippings generated by lawn mowing on-site rather than bagging the clippings for disposal or composting.

What is "grasscycling?"

Grasscycling is a simple and natural approach to lawn care. Clippings are left on the lawn after mowing to decompose quickly, releasing valuable nutrients back into the soil. Grasscycling has many benefits: it saves time, money and the resources needed to pick up and handle the clippings for composting or landfilling. When practiced in conjunction with proper lawn management, grasscycling can reduce water and fertilizer requirements, mowing time, and disposal costs.

Estimating generated volumes of grass clippings

• EPA/Tellus Institute estimates the combined source reduction potential of grasscycling and composting of yard trimmings to be 18.3 million tons, or 8.8 percent of the total national solid waste stream.
• The California Integrated Waste Management Board uses a figure of 704 pounds of grass clippings generated per single family house per year.
• The University of California has calculated the generation of grass clippings at 300 to 400 pounds per 1000 square feet of lawn per year.
• Metro estimates that grass clippings constitute up to 50 percent of the total yard trimmings generated in the Portland metropolitan region between March and October.

Facts about grass & grass clippings

• Grass clippings are 75 percent to 85 percent water. When you mow regularly, they quickly decompose and release nutrients to fertilize the lawn.
• The nitrogen contained in grass clippings almost equals the recommended application rate for healthy turf (5 pounds of nitrogen per 1000 square feet per year). While some of this nitrogen is lost through the decomposition process, grasscycling can have the overall impact of reducing fertilization requirements by 25 percent or more.
• Grass clippings do not cause thatch. Thatch is a tightly intermingled layer of living and dead stems, leaves and roots of grass that develops between the green grass and the soil surface and is caused by short, frequent watering.

Healthy lawn maintenance practices

• Water infrequently (weekly) and deeply (six to eight inches) with one inch of water when necessary. Use an empty tuna can to measure the amount of water provided.
• Water during the cooler parts of the day, like in the early morning or late afternoon, to reduce water loss due to evaporation. Avoid watering too late in the day, when the grass is unable to dry off. Damp grass invites diseases.
• Stay off the grass while the lawn is wet. Wet soil compacts more easily, and grass does not grow well in compacted soil.
• Mow only when the grass is dry. Wet grass cuts poorly, clumps and spreads diseases more easily. If the lawn is too long or wet, use clippings in your compost pile or as mulch.
• A sharp blade is a must. Dull blades rip and tear grass, encouraging disease and browning of your lawn.
• Mow at least once a week and reverse the mowing direction every other time you mow. Generally you should cut your grass to about two inches, do not remove more than 1/3 of growth at one time.
• Any lawnmower can grasscycle. All you need to do is remove the bag! However, if your mower does not have a safety flap covering the opening where the bag fits into the chute, or a plug for the chute, contact your local retailer to purchase a retrofit kit. Do not compromise your mower's safety systems.
• Dedicated mulching mowers, both gas and electric models, do an outstanding job, even under wet conditions. They recirculate the clippings, chop them very finely, and blow the resulting mulch down into the lawn. There are no clippings to see or to track into the house.

Planning a grasscycling program for your jurisdiction

• Promotion: this is the most critical element to a successful program. Put a lot of thought into this. Identify the specific audience you want to reach. Tailor your message to that audience. Match the appropriate media that will reach your audience: print, radio, TV? Look for opportunities to piggyback on existing events, e.g. the County Fair, Home Improvement Show, Easter Egg Roll. For detailed information on how to promote a program, please see Residential Backyard Composting.
• Demonstration: consider having a grasscycling demonstration site in conjunction with a composting demonstration site, or demonstrate grasscycling on a lawn in the center of town, in front of the library or the County Offices, in Main Street Park, etc.
• Lawnmower Retailers and Manufacturers: contact them ahead of time to solicit their participation and/or sponsorship. They may be willing to offer a rebate on electric mulching mowers or push mowers.
• Technical Assistance: contact your local Oregon State University Extension Service, Master Gardener Program (see blue pages in your phone book). They may be able to staff the demonstration site or give a workshop on grasscycling.
• Educational Materials: see below for ideas and suggestions.

Written background documentation

• Carl Woestwin, "Evolution of home-based strategies for residential organics," BioCycle, May 1998, 37-39.
• Roger M. Guttentag, "Recycling in Cyberspace, Grasscycling,", Resource Recycling, June 1998, 50-52.
• Ohio State University Extension Fact sheet
• Grasscycling!, Make the Most of Your Lawn, Make the Most of Your Time
  California Integrated Waste Management Board, Waste Prevention World.

Referrals to existing programs

• Metro Recycling Information, 503-234-3000
• City of Eugene, 541-682-6830
• Seattle Public Utilities, Seattle, WA., 206-684-4684;
• Charles Reighart, Baltimore County, Department of Public Works, Towson, MD, 410-887-2000

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