Carefully planned grazing can increase native grasses and restore grassland overtaken by exotics, according to recent research at the TomKat Ranch in California. Like Dixon Ranches, TomKat Ranch practices Holistic Management.
From an article about the grazing study in Conservation magazine:
According to the experimental paradigm, the density of cattle was increased by subdividing the grazing area into sub-units. The cattle were allowed to graze in one area for a specified period of time (between one day and one week), and were then shifted to the next area. Each paddock therefore received between 70 and 120 days of rest in between grazing periods. This went on for two years. In July of 2011, 2012, and 2013, the researchers surveyed for native grasses.
The proportion of “vegetation survey units” that included native grasses at all increased from 8% in 2011 to 80% in 2013. The surface area covered by native grasses remained small throughout the study (less than 5%), but increased significantly over time. In 2011, the researchers spotted only single, dispersed, individual grasses from among the native species. By 2013, they found a number of small but dense patches, each containing multiple individuals.
The gains made by the native grasses were meager, but promising. The results convincingly suggest that switching from season-long open-ended continuous grazing to a more rigorous planned schedule will facilitate the restoration of California’s grassland.
This short video from NBC Bay Area explains more about the research, which was published in Ecological Restoration.
