Posted: Thursday, October 13, 2011 11:00 AM
Doug Warnock/For the Capital Press
Allan Savory shows us the composition of the soil at the Africa Centre in Zimbabwe.
Holistic approach, animal impact can benefit ecosystem
By Doug Warnock
For the Capital Press
Examples of the healing action of animal impact were shown to me in my recent visit to the African Centre for Holistic Management near Victoria Falls, Zimbabwe.
The Centre is located on the Dimbangombe Ranch managed by Allan Savory and his wife, Jody Butterfield. Savory introduced holistic management, a sustainability-focused decision-making process that is being adopted by more land managers every year. He established the African Centre in 1989 to help land managers recover their land from the desertification process, which increased soil erosion, reduced effective water cycling and destroyed productivity.
The ranch is a living classroom in that it demonstrates the benefits from planned grazing. Bare soil that couldn't effectively hold water and produced very little grass for grazing animals was encountered by Savory when he took over operation of the ranch. Under his management, perennial grasses cover most of the soil that was previously bare and the Dimbangombe River, which flows through the ranch, is gaining in the volume and reach of its water.
Holistic planned grazing
The change that has happened on this ranch comes from a holistic approach to planned grazing. The area in which the ranch is located is dry through about eight months each year. During the Zimbabwe summer, starting in November, heavy rains occur. If the soil is bare during the rainy season, much erosion takes place and the river basins are filled with silt washing down from the uplands.
Prevention of this loss of topsoil requires maintaining a good ground cover of the deeper-rooted grasses. The cattle grazing is done according to a planned schedule that allows them short-term access to the grass plants and does not return them to an area until the grasses have recovered and grown back.
This grazing process involves a high density of animals for a short duration. The hoof action of the cattle breaks up the hardened soil surface and integrates organic matter into the soil. At the same time, the depositing of the cattle's dung and urine adds vital minerals to the soil.
This results in soil that has higher organic matter content, is more porous and able to retain moisture, has a healthier population of soil organisms and is very supportive of deep-rooted, perennial grasses. This kind of management works around the world and its success has been well demonstrated in the western United States.
Benefits to wildlife
With this healthier ecosystem, wildlife becomes more abundant. Several species of game animals and birds that had become scarce before the management change have increased in number, because of the greater amount of feed, water and shelter that is now available.
Indeed, wildlife is a major interest for Savory. He began his post-university life as a game reserve manager and became concerned when game herds began to run short of feed. In attempting to solve this dilemma, he developed this holistic approach to management.
Doug Warnock, retired from Washington State University Extension, now lives on a ranch in the Touchet River Valley where he consults and writes on ranch management.