Effects of Ovine Grazing as a Estrategy for the Control of Privet (Ligustrum lucidum W.T. Aiton)

Invasive species have spread, overcoming dispersion and adaptation barriers. These invasions affect ecological functions and economic activity, especially in areas close to urban centers. In Uruguay, species such as Ligustrum lucidum (privet) threaten native forests, highlighting the need for research and collaboration for their control. Directed grazing is suggested as a potentially effective tool to control invasive species. To evaluate the effectivity of livestock grazing as a strategy for privet control, a study was conducted at Las Brujas Experimental Station of the National Institute of Agricultural Research (INIA) in Canelones, Uruguay. Six plots of 0.04 hectares each were established in an area invaded by privet, divided into two blocks with different tree coverages. Using a completely randomized block design, the effects of sheep grazing on privet control were evaluated. Variables such as plants number, height, number of leaves, presence of apical bud and cut buds were recorded before and after the grazing period. At the end of the experiment, grazing reduced the total number of plants and apical buds, especially in plants less than 25 cm tall. Sheep grazing emerges as a promising alternative for privet control by reducing chemical use and costs. However, a single grazing period is not enough to drastically reduce the privet seedlings population. Further research is needed to examine the effects of higher stocking rates or different breeds and to assess the long-term impacts of sustained grazing on the same area.