By Pat Hoelter, Colorado State University Cooperative Extension Master Gardener, Denver County
You might not know if the sheep or peat or topsoil you are buying to amend your soil contains Colorado mountain peat, a slow-forming, non-renewable natural resource. Its extraction from mountain lands leads to erosion and other problems that can be harmful to the environment. A better deal, however, is home-grown compost, which is superior to peat for soil improvement.
Mixing good quality organic matter such as compost into soil holds open the space expanded by spading or rototilling. This type of soil improvement is the name of the game for growing healthy roots and healthy plants in Colorado. Unlike peat, compost is renewable and the nutrients and acid/alkaline balance can be manipulated.
Colorado's high country peat is formed in small basins carved by the last ice age and in abandoned river beds at altitudes of 8,000 to 12,000 feet.
Peat lands are made from layers of sedges, rushes, grasses, wildflowers and herbaceous wetland plants include Rocky Mountain iris, pale blue-eyed grass, shooting star and aquatic Siberian gentian. Some of these plants exist in isolated populations not found anywhere else outside of Canada and Alaska. Colorado may be one of the few places where some rare peat land plants have adapted to a warmer environment.
Scientists estimate the age of most Colorado pet deposits at between 4,000 and 10,000 years. In our climate, peat accumulates very slowly at rates of only two-and-one-half feet every 3,000 to 5,000 years.
Excavation of peat upsets the natural hydrologic balance of mountain ecosystems by changing surface and ground water flow. Resulting runoff and erosion affect water quality. Aquatic organisms are adversely affected and wildlife habitats and species can be altered or eliminated. Scientists believe peat lands are difficult if not impossible to reclaim because of climate warming over thousands of years. Today's conditions simply don't favor peat wetland formation
Gardeners who want to preserve Colorado's high country ecology and who also want too obtain the best quality material for improving their garden soil should ask questions before purchasing organic material. Or, they should make their own compost.
(Thanks to the Colorado Native Plant Society for its research help for this article.)
Photo: courtesy of the EPA
© CSU/Denver County Extension Master Gardener 2010
888 E. Iliff Avenue, Denver, CO 80210
Date last revised: 01/05/2010