"Innovations" Case Studies: Organics Options

General Information

• What Are Organic Materials?
• Organic Materials Reduction and Reuse

What Are Organic Materials?

Organic materials include yard trimmings (for example, tree trimmings and grass clippings), discarded food (and food-contaminated paper), wood debris from construction and demolition projects, stumps and large logs, gypsum wallboard, reusable lumber, rebuildable pallets, manures (horse and zoo), and crop residues. Waste prevention and reuse, recycling, and composting programs can dramatically decrease the amount of organic materials being landfilled.

In 1990, more than 90 percent of all these organic materials were disposed in landfills. Other organic materials such as biosolids also contribute to landfills, but they are not the focus of this report. By 1995 California was diverting about 3 to 5 million tons of organic materials, but the majority of organic materials were still disposed in landfills. A significant increase in organic materials diversion is needed if the 50 percent landfill diversion mandate is to be met on a statewide basis.

In its 1997 strategic plan, the California Integrated Waste Management Board (CIWMB) identified organic materials as a key to meeting waste diversion goals of the Integrated Waste Management Act (AB 939, Sher, Chapter 1095, Statutes of 1989 as amended [IWMA]).

Most municipalities in California have implemented some form of organics recycling programs. In fact, communities are finding that organics reuse, recycling, and composting programs are diverting from landfills as least as much waste as the much-heralded curbside recycling programs.

In addition, these materials are high in moisture content and contribute significantly to the generation of methane and leachate from landfills. By diverting these wastes from landfills, communities are decreasing the amount of moisture in landfills. This is critical to the optimal operation of today’s landfills and to decreasing landfill impacts on global warming and climate change.

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Organic Materials Reduction and Reuse

As in all aspects of solid waste and environmental management programs, the lowest cost option is conservation. Generally, 80 percent of the costs of recycling and solid waste management are in the materials collection. Programs that use materials on-site or do not produce the waste can contribute those savings directly to the household or business participating. For local government organics programs, that means promoting the following:

• Home composting
• Grasscycling and mower programs
• Food donations
• Xeriscaping

Practices that reduce the amount of green waste yield significant economic and environmental benefits. Direct savings include reduced maintenance, labor, water, and fertilizer cost, and reduced hauling and disposal fees. On-site management of yard trimmings returns valuable high-quality nutrients and organic matter to the soil. This encourages healthier disease and pest-resistant plants that improve appearance, prevent erosion, and increase property values.

Home Composting

Composting is a biological process by which plant and other organic materials are decomposed under controlled conditions. Bacteria, fungi, other microorganisms, and worms help break down the material. The finished product is a dark brown, decomposed form of organic matter similar to the organic matter in soil.

Many types of organic materials can be composted-grass clippings, manure, leaves, weeds, corn stalks, pine needles, sawdust, wood ashes, and many other kinds of plant refuse. Branches and twigs should be chipped before composting, or they will decompose very slowly.

Most communities in California promote home composting as part of their educational programs. Many communities provide additional incentives by providing free or discounted home composting bins to residents. San Mateo County provides subsidies to residents to purchase backyard bins and has sold more than 10,000 bins to date. Seattle has reported more than 43 percent of the public is participating in the city’s home composting program after eight years of outreach efforts.

Compost bin sales are conducted as one-time events or as a routine service of the community. One-time events are often organized in a parking lot, and bins are sold from the back of a manufacturer’s truck at wholesale and subsidized prices.

In Santa Cruz County, 15 percent of all households obtained home composting bins from the hauler or from parking lot sales. Discounted bins are sold to customers at cost if they also want yard trimmings collection services.

In a unique rate incentive, Santa Cruz offers residents a limited service option, which includes a 20-gallon can for weekly garbage service, three stacking bins for recyclables, and no yard trimmings collection. Free home compost bins were distributed instead of providing yard trimmings collection for these customers. Free bins included 2,100 Earth Machine backyard composters and 600 Can-O-Worms worm composters.

Santa Cruz County found that active composting households were much more likely to subscribe to the smallest level of garbage service under this rate incentive. They estimate that these active households averaged 45 pounds of yard trimmings and discarded food recycled per week, or about a ton each year.

In another innovative community program, the City of Glendale provides $50 rebates on the purchase of home chipper/shredders, a Consumer Reports evaluation of reasonably priced chipper/shredders, and information on additional retailer discounts. In addition, the city purchased its own chipper/shredder and offers a free service to residents to bring yard trimmings to a city site for shredding. The shreds are then made available for residents.

Other cities have used a full-size mobile chipper (like those of tree trimming companies) to provide yard trimmings chipping services to residents at their homes. In one case, they offer the option to the resident of leaving the shredded material on the curb for the homeowner to use as mulch, or to take it away.

Grasscycling and Mower Programs

Grass clippings make up a surprisingly large portion of California’s waste stream. During peak growing seasons, up to 7 percent of the waste stream is grass clippings, or several million tons each year. Grasscycling offers a simple alternative: just leave clippings on the lawn when mowing.

Grasscycling actually requires less work than raking up clippings and putting them in a bag or at the curb for pickup. Grasscycling is the natural recycling of grass; grass clippings decompose quickly and release valuable nutrients back into the soil. University studies have shown that grasscycling is not harmful to lawns when they are cared for properly. In fact, grasscycling has long been a common practice on large grass areas such as parks, golf courses, and sport fields (locations where clippings collection is not feasible).

The basics of grasscycling are:

• Water and fertilize in moderation.
• Keep mower blades sharp.
• Cut when the grass is dry.
• Cut no more than one-third of grass height at once.

The CIWMB established grasscycling demonstration sites at the State Capitol in cooperation with the building and grounds office of the Department of General Services. The grounds crew was so pleased with the resulting time and money savings that they converted their entire fleet to grasscycling mowers.

The CIWMB and local governments are partnering in many locations to promote grasscycling techniques. The CIWMB has held many workshops around the state, targeting landscapers and other professionals in the field.

In addition, some communities are now partnering with manufacturers of grasscycling mowers. Communities promote the purchase of grasscycling mowers, and the companies provide discount coupons for purchase of grasscycling mowers for the communities to distribute.

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Food Donations

Donation of edible food to charities is the highest and best use of this resource. America’s Second Harvest is a national network of 200 food banks that distribute donated food through 50,000 charitable agencies to hungry Americans. That network serves all 50 states and Puerto Rico. Their goal is to end hunger in America.

Last year, one billion pounds of food was distributed through the America’s Second Harvest network, feeding 26 million hungry Americans. Eight million of these are children (that means one in five people in a soup kitchen line is a child).

Many communities have prepared lists of food donation opportunities in their areas or included those in general lists of recycling opportunities. In some communities, they have also assisted the food donation businesses to improve the services they offer, including purchase of necessary vehicles and equipment.

In San Francisco, the food bank collects and redistributes edible discarded produce and other food. The city helped the food bank with several grants made from 1996 to 1999. These included funds for a refrigerated truck and a partial year’s salary for a driver ($97,100 in 1996), a forklift and pallet jack ($44,000 in 1997), a sorting conveyor system ($55,000 in 1998), and a refrigerated truck and pallet jack ($62,500 in 1999).

The San Francisco Food Bank collects edible food from wholesalers at the San Francisco Produce Terminal and other wholesalers in the city. Participating businesses benefit from the program by reducing their garbage costs and claiming a tax deduction for donated food.

The food bank collects food in its original packaging, as long as it is mostly edible, and transports it in a refrigerated truck to its warehouse where volunteers separate edible food from inedible food. More than 70 percent of the produce collected is delivered directly to member organizations that feed thousands of people daily in San Francisco.

San Francisco’s first Kids Cafe is a good example of America’s Second Harvest programs targeted at children in need. The San Francisco Food Bank opened a Kids Cafe in the Bayview Hunters Point Community Center, which serves a neighborhood that has one of the highest rates of childhood poverty in the city. The community center provides children with after-school programming in science and technology, art, dance, ceramics, and academic tutoring. Kids who visit the center can also sign up to be amateur chefs, helping to prepare and serve meals for other kids.

Xeriscaping

Xeriscaping is a landscape practice designed to decrease water use. Xeriscaping also can reduce the amount of waste from growing plants and the amount of time devoted to weeding, pruning, and watering landscaping. Xeriscaping also limits the need for pesticides as it encourages integrated pest management for pest control.

The key to xeriscaping is selecting what to plant. Trees and shrubs that are native to California are often drought-tolerant and slow-growing. These plants will generally produce less waste and require less water. Lists of native plants in your area can be obtained from local master gardeners or most professional nurseries.

Xeriscaping also considers the mature size of plants and ensures that the plants match the location. The use of both winter and summer perennials can give year-round color without the cost and waste of replacing annual plants. Installation of perennial ground covers that do not require replacement every year can be an attractive alternative to turf and result in a reduction of yard trimmings.

To ensure that these plants prosper, the nearby soil needs to be kept free of competing plants, which can be done with composted wood chips, pine needles, fine gravel, or other recycled materials. Mulching provides ideal moist conditions for healthy microorganism and macroorganism populations. The use of compost improves soil structure, texture, and aeration. It also improves moisture regulation and provides slow-release nutrients that feed plants on a constant basis.

Xeriscaping encourages improvements for soil, including lowering its pH. Xeriscaping also allows for shading (which reduces water needs) and planting just before or after the rainy season.

Communities could require xeriscaping to be used in new developments as conditions of local land use permits. Communities could also require xeriscaping practices to be used on all public facilities.

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Last updated: October 26, 2007