Caswell Memorial State Park

Caswell Memorial State Park is a state park of California, United States, preserving a riparian forest along the Stanislaus River. It is located in southern San Joaquin County southwest of the town of Ripon. Riparian Oak Woodland, located in this park, is threatened and the park is trying to protect it. It once flourished through California's Central Valley. Caswell is also the home to several endangered species. The 258 acre park was established in 1952.

The average temperature is 45 - 50 F in the winter and 85 - 100 F in the summer. It is common to exceed 100 °F for several consecutive days in the summer. Caswell is home to many mosquitoes.

This park has been named after the landowner, Thomas Caswell. He enjoyed this beautiful forest and wanted to preserve it. In the 1950s, 134 acre of this forest were donated by his children and grandchildren to California before it was opened to the public as a state park in 1958.

The riparian brush rabbit (S. b. riparius) is listed as an endangered species by the United States Fish and Wildlife Service. Formerly numerous along the San Joaquin River and Stanislaus River, it is now reduced to a population of a few hundred here and was reintroduced to the adjacent San Joaquin River National Wildlife Refuge. This population has been negatively impacted by the destruction of the riparian habitat.