California Central Valley

Flora

The Central Valley was formerly a diverse expanse of grassland, containing areas of prairie, desert grassland (at the southern end), oak savanna, riparian forest, marsh, several types of seasonal vernal pools, and large lakes such as now-dry Tulare Lake (once the largest freshwater lake west of the Mississippi), Buena Vista Lake and Kern Lake. However, much of the Central Valley environment has been altered by human activity, including the introduction of exotic plants, notably grasses. The valley's grasslands, wetlands, and riparian forests constitute the California Central Valley grasslands, a temperate grasslands, savannas, and shrublandsecoregion. The foothill oak woodlands and chaparral that fringe the valley have been categorized as the California interior chaparral and woodlands ecoregion.