Rehabilitation of degraded rangelan

Rehabilitation of degraded rangelands has been attempted on extensive areas.Rehabilitation efforts are expensive and the benefits are not accrued for a sufficient period of time to recoup the expenditure. For example, between 1940 and 1981, an average of 600,000 ha of brush-infested rangeland in Texas was treated annually by herbicides, fire,and mechanical means such as root plowing, chaining, and disking (Rappole et al., 1986).Despite the intensity of treatments, land managers realized only a transitory, short-term gain in productivity. Regrowth of shrubs occurred in less than a decade, and retreatment becamenecessary within 15 years of root plowing, 2 years after chaining, and 8 years after treatment with herbicides (Rappole et al., 1986). Similar results have been reported in other desert rangeland areas (Herbel et al., 1983). Even when combined with exclusion of livestock grazing, root plowing and herbicide treatment has not resulted in reestablishment of grassland (Chew, 1982; Roundy and Jordan, 1988). In the United States, restoration practices are shifting toward restoration practices that are large and expensive plus related to fire and invasive species control (Copeland et al., 2018)