The Vina Plains is an excellent example of California annual grasslands and vernal pools on the upper terrace of the Sacramento Valley. The shallow soils are underlain by an impervious, rocky hardpan formed by volcanic mudflows a million or more years ago. Subsequent erosion has scoured out shallow depressions that fill with water during the rainy season. Because of the impermeable subsoil, the water remains until it is lost by evaporation late in the spring. These temporary ponds support a wide variety of plants, crustaceans, snails, flatworms and insects. During winter the ponds attract legions of waterfowl and shorebirds. Songbirds such as meadowlarks and horned larks nest in the grasslands and raptors can be viewed hunting overhead.
Why TNC Selected This Site
Vina Plains is an important property for The Nature Conservancy in the Lassen Foothills area. Vernal pools at the Preserve are some of the best remaining in California. Although once common in the Central Valley and other parts of the state, vernal pools have been reduced to less than 5% of their original range and are now one of California's most threatened natural communities. On a broader scale, the Preserve is part of a massive unfragmented landscape where the state’s largest migratory deer herd roams. Major creeks in the region host some of the state's best remaining salmon runs.
What TNC Is Doing
We actively manage this landscape with seasonal cattle grazing and prescribed burning. Each spring The Nature Conservancy supports a prescribed burn led by Cal Fire at the Preserve. These disturbances support native flora and help to keep nonnative annual grasses under control. Vina Plains offers a prime outdoor classroom for students and researchers alike. Researchers have studied the Preserve’s rare species and vernal pool habitats for decades, resulting in dozens of scientific publications. The public may visit on any of several organized annual tours each spring.