Ledson Marsh
Encyclopedia
Ledson Marsh is a 30 acre (0.1214058 km²) freshwater marsh
in Annadel State Park
east of Santa Rosa
in Sonoma County, California
, United States
. Located on the east flank of Bennett Mountain
, it drains into Schultz Creek, a tributary of Yulupa Creek
.
The marsh was formed by an earthen embankment dam about 300 feet (91.4 m) long, constructed in 1930 by a former landowner. The dam is about 6 feet (2 m) high and 4 feet (1.2 m) wide at its crest. Over the years, the dam deteriorated, allowing water to seep through it and causing the marsh to dry out in the autumn and refill during the winter rains. The deterioration was partly due to rodent holes and partly due to stumps left by the felling of eucalyptus trees that were planted on both sides of the embankment.
Because of its seasonality, the marsh was colonized by California Red-legged Frog
s, a threatened species
. Government agencies grew concerned that if the marsh did not dry out every year, bullfrogs might establish themselves in the marsh, displacing the red-legged frogs. At the same time, there was concern over the dam's safety. A catastrophic dam failure would destroy the marsh habitat and clog various Sonoma Creek
tributaries with sediment. The California Department of Parks and Recreation
therefore repaired the dam in such a way as to preserve the marsh's seasonality.
The marsh is also a picnicking and bird-watching spot and a landmark for mountain bicyclists, hikers, joggers, and equestrians.
Marsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....
in Annadel State Park
Annadel State Park
Annadel State Park is a state park of California, USA, situated at the northern edge of Sonoma Valley and offering many recreational activities within its property...
east of Santa Rosa
Santa Rosa, California
Santa Rosa is the county seat of Sonoma County, California, United States. The 2010 census reported a population of 167,815. Santa Rosa is the largest city in California's Wine Country and fifth largest city in the San Francisco Bay Area, after San Jose, San Francisco, Oakland, and Fremont and 26th...
in Sonoma County, California
Sonoma County, California
Sonoma County, located on the northern coast of the U.S. state of California, is the largest and northernmost of the nine San Francisco Bay Area counties. Its population at the 2010 census was 483,878. Its largest city and county seat is Santa Rosa....
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Located on the east flank of Bennett Mountain
Bennett Mountain
Bennett Mountain is a summit in the Sonoma Mountains of California. Located on the west edge of Annadel State Park, it separates Bennett Valley in the Russian River drainage basin from Sonoma Valley in the Sonoma Creek drainage basin....
, it drains into Schultz Creek, a tributary of Yulupa Creek
Yulupa Creek
Yulupa Creek is a southeast-flowing perennial stream that rises on the southeastern flanks of the northern Sonoma Mountains in Sonoma County, California, United States...
.
Because of its seasonality, the marsh was colonized by California Red-legged Frog
California Red-legged Frog
The California red-legged frog, Rana draytonii, is a moderate to large species of frog. It is known under the scientific name Rana draytonii, after being long included with the northern red-legged frog The California red-legged frog, Rana draytonii, is a moderate to large (4.4–14 cm) species...
s, a threatened species
Threatened species
Threatened species are any speciesg animals, plants, fungi, etc.) which are vulnerable to endangerment in the near future.The World Conservation Union is the foremost authority on threatened species, and treats threatened species not as a single category, but as a group of three categories,...
. Government agencies grew concerned that if the marsh did not dry out every year, bullfrogs might establish themselves in the marsh, displacing the red-legged frogs. At the same time, there was concern over the dam's safety. A catastrophic dam failure would destroy the marsh habitat and clog various Sonoma Creek
Sonoma Creek
Sonoma Creek is a stream in northern California. It is one of two principal drainages of southern Sonoma County, California, with headwaters rising in the rugged hills of Sugarloaf Ridge State Park and discharging to San Pablo Bay, the northern arm of San Francisco Bay. The watershed drained by...
tributaries with sediment. The California Department of Parks and Recreation
California Department of Parks and Recreation
The California Department of Parks and Recreation, also known as California State Parks, manages the California state parks system. The system administers 278 parks and 1.4 million acres , with over of coastline; of lake and river frontage; nearly 15,000 campsites; and of hiking, biking, and...
therefore repaired the dam in such a way as to preserve the marsh's seasonality.
The marsh is also a picnicking and bird-watching spot and a landmark for mountain bicyclists, hikers, joggers, and equestrians.