Use of Goats for Vegetative Control on Military Landfills
Hoddinott, Keith
Environmental Health Risk Assessment Program, U.S. Army Center for Health
Promotion and Preventive Medicine, Aberdeen Proving Ground, Maryland, USA 21154
The control of vegetation on landfill covers represents a significant part of the expense of long term maintenance. Best management practices and state regulations require that vegetative landfill covers be maintained to reduce erosion and percolation into the refuse fill. The best systems use grass vegetative covers to decrease erosion and increase evapotranspiration while limiting rooting depth and avoiding penetration of the cap which would allow percolation into the refuse. Maintenance of the cover offers the challenge of promoting grass growth while eliminating the growth of species with deeper root systems. Currently most landfill operations use a schedule of mowing and application of broad leaf herbicides to control both vegetative species and growth rates.
Estimates of $30-$40 per acre per mowing with 3-4 mowings per year for at least 30 years result in a cost of $2700-$4800 per acre with no beneficial return. Over the years, people have touted the benefits of using livestock in a rotational grazing operation to control cover vegetation, reducing or eliminated cost while providing a beneficial return.
Goats have an advantage over other grazing animals due to their less selective diet and their preference to consume broad leaf vegetation. This attribute impedes the natural succession of grass land to brush, tall shrubs, trees and other plants roots that penetrate deep into the subsoil. This study identifies the benefit and disadvantages of using goats as well as examines the requirements for converting landfill covers to rotational grazing paddocks. Examples from Kentucky and Pennsylvania are examined to determine their applicability to use on military posts. Consideration is given to grazing strategy, loading rates, nutrient management, parasite management, predator control, and landfill regulatory requirements as they relate to post operations.