Overgrazing is excessive grazing of plants by wildlife or livestock. Overgrazing occurs when too much green material is repeatedly removed from a plant and it does not have sufficient leaf mass to regrow. Residual plant matter is needed to hold the soil and prevent erosion by water or wind. Overgrazed rangeland is often characterized by an increase in weeds or unpalatable plants, increased soil erosion, and a decrease in the biomass of important forage plants. Rangelands typically receive less precipitation than more productive farmland, and have few or low growing plants which shouldn't be confused with an overgrazed site. Overgrazing should not be confused with overstocking. Overstocking is when a site is heavily stocked with more animals than the site could support for a grazing season, such as is often the case with targeted grazing. However, poor management coupled with overstocking can severely degrade a site.