Study Sites

This page lists the butterfly monitoring sites in this study and their respective characteristics.

Castle Peak

High Sierra. Subalpine and alpine vegetation; tree-line of Mountain Hemlock, Lodgepole Pine, Western Whitebark, and White Pine; persistent snow fields, boggy seeps, and wet meadows.

Donner Pass

High Sierra. Montane communities with local subalpine elements; granite balds with herbs and low shrubs; mature Red Fir forest; large wet and dry meadow complex with a few boggy spots, fringing Willows and Mountain Alders.

Gates Canyon

Inner Coast Range foothill canyon. Vegetation includes: Interior Live Oak woodland, Blue Oak woodland, chaparral, Gray Pine, and riparian forest of Cottonwood, Bigleaf Maple, and Alder.

Lang Crossing

West-slope Sierra Nevada. Mosaic of xerophytic vegetation (Goldencup Oak and Manzanita) and moist slopes with mixed mesic forest (including Douglas Fir, Ponderosa Pine, and Sugar Pine); site also includes a large wet meadow with boggy areas.

North Sacramento

Central Valley Floor. Valley Oak woodland; riparian Cottonwood and Willow; annual grassland.

Rancho Cordova

Eastern edge of Central Valley. Interior Live Oak-Gray Pine woodland, Valley Oak-dominated riparian forest, and annual grassland.

Sierra Valley

East side of Sierra. Wet and dry meadows with Juniper-shrub steppe and irrigated alfalfa fields.

Suisun Marsh

Tidally-influenced complex of brackish and freshwater marsh. Plants include halophytes, sedges, rushes, cattails, reeds, and herbaceous perennial composites.


Sierra Foothills. Deep canyon with mixed serpentine and metasedimentary geology. Canyon Live Oak woodland with mesic mixed lower-montane forest including Douglas Fir, Incense Cedar, and Ponderosa Pine.

West Sacramento

Central Valley Floor. Dense riparian Cottonwood and Willow forest with Valley Oak and Ash.

Willow Slough

Willow Slough is the name for the sampling route of my Fourth of July Butterfly Count (program run by the North American Butterfly Association). It comprises California annual grassland, some riparian vegetation, and a channelized floodplain whose vegetation has varied over the sampling years depending on seasonal flooding, fire, and management for flood control. It is basically a combination of annual and perennial floodplain vegetation with riparian and tule-marsh elements.