I’d like to use berms to partition my yard into two smaller gardens and to increase privacy. Is there any reason not to use a large pile of tires as a foundation to build them on? It would be a great way to recycle old tires.
Marcia Sweet, Ottawa, Ontario, ca
Robert Gillmore, a landscape designer in Goffstown, New Hampshire, and author of The Woodland Garden, replies: There are a number of reasons not to use a large number of old, rubber tires as a foundation when building a landscape berm. In a large berm made up of a mixture of old tires and soil, the air spaces inside and between the tires would provide comfortable nesting areas for rats and other pests. As the tires decayed, the air spaces would be compressed by the soil, and the berm would slowly collapse. Also, the petroleum emitted by a large number of decaying tires would eventually seep into the groundwater in the area. For these and other reasons, most jurisdictions require that tires be dumped only at landfills or other solid waste disposal sites.
To ensure stability over the long run, I recommend using such non-decaying materials as sand-clay fill, large rocks and gravel. These readily available materials allow for drainage, while providing a sturdy and ecologically sound foundation for landscape berms.