Los Guillicos Preserve

At the time of first contact with Europeans, there was a large marsh complex (about 400 acres/162 ha) that stretched from present-day Pythian Road (just south of the Preserve) through Kenwood and into Glen Ellen.

[3] This highly productive habitat likely provided the Wappo with abundant food (e.g. coho salmon, steelhead, waterfowl) and resources.

The Wappo were one of the few tribes to successfully resist military takeovers by the Spanish, but they succumbed to the cholera and smallpox epidemics of 1833 and 1838.

By the late 1800s, valley ditches were common and connections had been created between all the major isolated tributaries and Sonoma Creek.

[2] In the late 19th and early 20th century, much of the local economy in the Sonoma Valley was driven by San Francisco's demand for resources.

Preserve lands are at the transition between valley floor (quaternary alluvial fan sediments) and foothills of the range.

Grasslands in the valley bottom include mature Douglas fir (Pseudotsuga menziesii) and black oak (Quercus kelloggii).

Bigleaf periwinkle (Vinca major) is particularly abundant at the lower elevations of the Preserve, invading grasslands beneath tree canopies.

Mountainous areas of the preserve include black oak (Q. kelloggii) and California bay laurel (Umbellularia californica).

[7] There are two barns at the entrance of the property just off Pythian Road which are used by the Sonoma County Wildlife Rescue under contract with SSU as a flight aviary for rehabilitating wild raptors.