King County Navigation Bar

King County Environmental Purchasing Program

Procurement Bulletin #12 - Recycled Materials for Landscape Applications


Introduction

This bulletin highlights ways in which landscape designers, gardeners, and homeowners can save money and improve performance with recycled and environmentally preferable materials and practices.


Northwest Flower and Garden Show

The King County Commission for Marketing Recyclable Materials, Department of Natural Resources hosted another successful demonstration garden at the 1998 Northwest Flower and Garden Show, in February. The show was attended by 85,000 people. This year's garden, designed by Phil Wood, introduced local gardeners and garden designers to several interesting and useful recycled materials. Among the items displayed were:

Please follow this link for a complete list of suppliers


Compost & Compost-Amended Topsoil

The peat-bogs of Canada, so long a source of cheap organic material for soil-amendment, are becoming depleted and peat is becoming increasingly expensive. Fortunately, many processors are producing high-quality organic soil-amendment materials from composts made from municipal yard-waste, biosolids, and farm wastes.

Compost resources on the internet:
Rot Web
Compost-Amended Topsoil at the West Point Treatment Plant
Vendors:
Cedar Grove Composting (206)763-2700 (yard waste compost)
Sawdust Supply (206)622-5141 (Groco - biosolids compost and SteerCo - manure compost)
Pacific Topsoils (425)337-2700

Landscape Mulch - Shredded Wood-Waste

Wood Waste from Construction, Demolition, and Landclearing (CDL) is shredded and used in many ways. Historically, it has been sold as raw material for paper-pulp, "hog-fuel," which is burned in cement kilns and other furnaces and for erosion-control. Several horticultural applications have recently been developed. As a landscape mulch it retains moisture, suppresses weeds, controls erosion, and contributes to soil tilth. As a soil amendment, it breaks down slowly and provides a lasting benefit to the structure of the soil (Soils amended with wood will initially require supplementary nitrogen for vigorous plant growth).

King County examples:

Landscape Mulch at the West Point Sewage Treatment Plant
A demonstration of shredded wood-waste at the King County Jail in 1995, led to a collaboration between the vendor and the West-Point wastewater treatment facility of the Department of Natural Resources. They developed a specification for a horticultural mulch and used 4,000 yards of this material for that project, saving over $6,000. The producer has opened a new market based on the product developed through that collaboration and is optimistic about future growth for this product.
 
Landscape Mulch at the King County Airport
In 1997, the King County Department of Construction and Facilities Management used 600 cubic yards of this material, at a cost of nearly $5,000, for a holding area for nursery-stock at the King County Airport, mulch around the Administration Building, and other applications.
Vendors:
Rainier Wood Recyclers (253)630-3565

Grasscycling

The King County Regional Justice Center is leading the way toward sustainable management practices by specifying the use of "mulching mowers" for the maintenance of RJC lawns. "Grasscycling" means leaving grass on the lawn after mowing. It can be done with any lawn mower, but mulching mowers produce very fine clippings which can be evenly spread and left in the lawn with a minimum of effort. Not only does this reduce the labor of raking, blowing and hauling, it also adds valuable nutrients to the lawn as the grass clippings break down. With these added nutrients, the lawn looks better and the owners may be able to reduce their use of fertilizer. This saves money and reduces the risk of fertilizers contaminating groundwater, streams, and the wastewater system.

Grasscycling resources on the Internet:
Grasscycling at the Regional Justice Center
Grasscycling - California Integrated Waste Management Board
Natural lawn care - King County hazardous waste program
6 steps to natural lawn care - City of Seattle

Grass Paving

Turf areas that receive heavy foot traffic, such as playfields, can benefit from a unique "paving" material made from recycled plastic, called Grasspave. This material consists of little plastic rings, fastened together and supplied in wide rolls, like carpet. First, the soil is prepared and grass-seed is sown, then the Grasspave is unrolled and the grass is allowed to grow up through the rings so that foot traffic or light vehicles will not crush the crowns of the grass-plants. The Grasspave web-site also features recycled plastic materials for other applications, such as wheelchair access to sandy beaches.

Vendor:
Invisible Structures, Inc. (800)233-1510

Plastic "Lumber"

Plastic "Lumber," made from recycled plastics, is available for many applications. Because it is unaffected by soil organisms and is non-toxic, plastic lumber is a useful and cost-effective substitute for chemically treated lumber in soil and water contact applications such as fence-posts, bollards, decking and retaining walls

King County's experience:

King County Roads, Solid Waste, and Parks Divisions have used plastic lumber picnic tables, benches, bollards, and side-boards for dump-trucks, and the Stadium saved money by using it for "channel boards" to secure the Astro-turf and "skid pads" to protect the legs of portable bleachers.
Bench Slats at Redondo Beach Park
Bollards, Roads Maintenance
Truck sideboards
Kingdome channel boards
Vendors (local):
White Cap Industries (206)581-2198 Seattle, WA (distributor for Hammer's Plastic)
Environmental Home Center (206)682-7332 Seattle, WA (distributor for various manufacturers)
MAUK Forest Products,(425)885-9808 Redmond, WA (distributor for Trex)
Northwest Recreation, (800)448-4858 (distributor for Eaglebrook)
Recycled Plastic Marketing (RPM), (425)867-3201 Redmond, WA (distributor for Earth Care Plastic)
Schrader Lumber (360)757-4417 Burlington, WA (distributor for Plastic Pilings)
Weyerhaeuser (800)562-0908 Kent, WA (distributor of ChoiceDek, AERT (wood/plastic composite))
 
please see vendor list for updated information

The Environmental Purchasing Program

The King County Environmental Purchasing Program assists County agencies in implementation of King County Executive Policy CON-7-1-2, which requires agencies to use recycled and other environmentally preferable products "wherever practicable."

The program assembles information about these products and makes it available to specific agency users who can evaluate them and attempt to develop applications in County projects.

These procurement bulletins contain information about the results of product evaluations and other accomplishments of County agencies. We hope this information will help you find ways to use recycled materials in the work of your agency and that you will contact us if we can help you with further information or if you have suggestions.


Environmental Purchasing Program
King County Procurement & Contract Services
821 Second Ave, Suite 10
MS:  EXC-FI-0862
Seattle, WA 98104
(206)263-4279
Published: March 5, 1998

Updated: June 25, 1998


King County | News | Services |

Links to external sites do not constitute endorsements by King County.
By visiting this and other King County web pages,
you expressly agree to be bound by terms and conditions of the site.
The details.