Millions of years of geology and evolution have created the spectacular vernal pools at Sacramento County’s Mather Field. These are exceptional examples of a rare wetland ecosystem that is unique to California. Visitors can experience this piece of California’s natural history, just 30 minutes from downtown Sacramento.
What is a Vernal Pool?
A vernal pool is a temporary wetland that fills with water during the rainy season and dries down in the spring. It remains dry for six to eight months awaiting the next winter rains. The plants and animals that are adapted to survive these annual extremes of flood and drought create a changing mosaic of life throughout the three phases of a vernal pool: wet, flowering and dry.
While the vernal pools at Mather Field range from 50,000 to
200,000 years old, the soils under them began forming more than
two million years ago. Dissolved minerals slowly moved down
through the soil, eventually forming a hardpan layer. This
hardpan lies a few inches to a few feet below the soil surface.
Although most vernal pool animals are small, their complex food
webs sustain many larger species of birds, mammals, amphibians
and reptiles. Most of the critters in vernal pools are native to
California and many survive only in vernal pools. We know little
about them and less than half have been named.
Over 200 plant species grow in vernal pools. Half of these are
rarely found outside this unique habitat. A single pool typically
supports only 15 to 20 species in an unpredictable array of
combinations. In that way, vernal pools are a lot like snowflakes
– botanically speaking, no two are alike.
Sacramento County intends to establish a vernal pool preserve at
Mather Field and manage it for the benefit of the hundreds of
resident plant and animal species. Access to some restricted
areas of the preserve is made possible through Splash public
programs. To learn more about visiting the Mather Field vernal
pools during their flowering period, go to April Flower Walks, or call
916-364-2437. Splash’s Nature in the
Neighborhood typically includes an outdoor adventure at
Mather Field as part of each program.
More than 90 percent of California’s vernal pools have been
destroyed. We hope you will take time to enjoy and protect those
that remain. For the benefit of future visitors and hundreds of
vernal pool species, please:
Explore the area only on foot – no bicycles or motorized
Avoid walking into or along the edges of vernal pools.
Keep dogs on leashes and out of restricted areas.
Leave all flowers for their pollinators and other visitors.
Unless you are on a guided tour, visit only areas open to the
We recently migrated our old site over to this spiffy, new
platform. Unfortunately, when you move a website, sometimes
things break. If something isn’t working or looks funny, please
fill out this quick form and we’ll fix it ASAP. Thanks for