Contemporary California grasslands can be considered a “novel” ecosystem. There is ongoing debate about what California grasslands once looked like, but historical records suggest they were a mix of annual wildflowers and perennial bunch grasses, such as California’s state grass, purple needlegrass (Stipa pulchra). Exact historical species composition remains speculative, because Spanish colonists brought annual grass seeds that took well to California’s Mediterranean climate. Those seeds spread to become one of the largest plant invasions of modern times – almost 9 million ha of California grasslands are now dominated by non-native species.
California rangelands consist of the portion of these grasslands that are actively managed for agricultural industries within the state. The forage produced within these lands support livestock operations from the coast to the foothills of the Sierras. While many of the Mediterranean grasses that now dominate California provide excellent forage, others are noxious weeds that place the abundance and quality of this grazing resource at risk.