Jasper Ridge Biological Preserve
Encyclopedia
The Jasper Ridge Biological Preserve is a 1,200 acre (5 km²) is a nature preserve and biological field station owned by Stanford University
, located at 37.408°N 122.2275°W south of Sand Hill Road and west of Interstate 280
in Portola Valley, California
. It is used by students, researchers, and docents to conduct biology research, and teach the community about the importance of that research. The preserve encompasses Jasper Ridge and Searsville Lake
(actually a reservoir) and the upper reaches of San Francisquito Creek
, along with the latter's Corte Madera Creek
and Bear Creek
tributaries.
and is bounded by San Francisquito Creek
, Corte Madera Creek
and Los Trancos Creek
, although the preserve occupies only the northwestern half of the ridge. The hilly mass runs about ten kilometers from northwest to southeast and about half that in width.
Serpentine (Serpentinite
) is the California State Rock. It was formed from deep sea or mantle rocks. This rock was squeezed toward the surface by tectonic plate movement, and thus feels greasy, as it has been polished over millions of years. Graywacke Sandstone after crossing Leonard's Bridge. This sandstone was part of the Franciscan formation 138 M years ago. Some rocks found at the preserve include: Greenstone, Chert, Serpentinite, Sandstone.
and Avena barbata
). However much of the grassland has been replaced by various oaks, especially Coast Live Oak
(Quercus agrifolia), and Pacific Madrone
(Arbutus menziesii). More recently, the oak/madrone forest is being succeeded
by specimens of large Douglas fir (Pseudotsuga menziesii) as in the image above. In addition there are several groves of second growth Coast Redwoods (Sequoia sempervirens) in the preserve, some in large "fairy rings" indicating that trees of immense girth were cut down in the nineteenth century.
s, an invasive species.
Stanford University
The Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...
, located at 37.408°N 122.2275°W south of Sand Hill Road and west of Interstate 280
Interstate 280 (California)
Interstate 280 is a 57-mile long north–south Interstate Highway in the San Francisco Bay Area of Northern California. It connects San Jose and San Francisco, running along just to the west of the cities of San Francisco Peninsula for most of its route.I-280 from its northern end at King...
in Portola Valley, California
Portola Valley, California
Portola Valley is an incorporated town in San Mateo County, California, United States. The population was 4,353 at the 2010 census. It was named for Spanish explorer Gaspar de Portola, who led the first party of Europeans to explore the San Francisco Peninsula, in 1769.Portola Valley is one of the...
. It is used by students, researchers, and docents to conduct biology research, and teach the community about the importance of that research. The preserve encompasses Jasper Ridge and Searsville Lake
Searsville Dam
Searsville Dam is a masonry dam that was completed in 1892, one year after the founding of Stanford University, and impounds Corte Madera Creek to form a reservoir known as Searsville Lake. Searsville Dam is located in the Jasper Ridge Biological Preserve and is owned and operated by Stanford...
(actually a reservoir) and the upper reaches of San Francisquito Creek
San Francisquito Creek
San Francisquito Creek is a creek that flows into southwest San Francisco Bay in California, United States of America. Historically it was called the Arroyo de San Francisco by Juan Bautista de Anza in 1776...
, along with the latter's Corte Madera Creek
Corte Madera Creek (San Mateo County, California)
Corte Madera Creek is a creek that flows north-northwest to Searsville Dam and then joins with Bear Creek to form San Francisquito Creek in California...
and Bear Creek
Bear Creek (San Francisquito Creek)
Bear Creek is a southeastward-flowing stream originating north of the summit of Sierra Morena in the Santa Cruz Mountains, near the community of Kings Mountain in San Mateo County, California, United States...
tributaries.
Geology
Jasper Ridge is part of the foothills northeast of the Santa Cruz MountainsSanta Cruz Mountains
The Santa Cruz Mountains, part of the Pacific Coast Ranges, are a mountain range in central California, United States. They form a ridge along the San Francisco Peninsula, south of San Francisco, separating the Pacific Ocean from San Francisco Bay and the Santa Clara Valley, and continuing south,...
and is bounded by San Francisquito Creek
San Francisquito Creek
San Francisquito Creek is a creek that flows into southwest San Francisco Bay in California, United States of America. Historically it was called the Arroyo de San Francisco by Juan Bautista de Anza in 1776...
, Corte Madera Creek
Corte Madera Creek (San Mateo County, California)
Corte Madera Creek is a creek that flows north-northwest to Searsville Dam and then joins with Bear Creek to form San Francisquito Creek in California...
and Los Trancos Creek
Los Trancos Creek
Los Trancos Creek is a creek that flows northerly from Monte Bello Ridge in the Santa Cruz Mountains to its confluence with San Francisquito Creek at Stanford University in California, United States of America...
, although the preserve occupies only the northwestern half of the ridge. The hilly mass runs about ten kilometers from northwest to southeast and about half that in width.
Serpentine (Serpentinite
Serpentinite
Serpentinite is a rock composed of one or more serpentine group minerals. Minerals in this group are formed by serpentinization, a hydration and metamorphic transformation of ultramafic rock from the Earth's mantle...
) is the California State Rock. It was formed from deep sea or mantle rocks. This rock was squeezed toward the surface by tectonic plate movement, and thus feels greasy, as it has been polished over millions of years. Graywacke Sandstone after crossing Leonard's Bridge. This sandstone was part of the Franciscan formation 138 M years ago. Some rocks found at the preserve include: Greenstone, Chert, Serpentinite, Sandstone.
Ecology
In 1922, Cooper asserted that Jasper Ridge was historically chaparral, and cleared in the nineteenth century to open grasslands, primarily Eurasian wild oats (Avena fatuaAvena fatua
Avena fatua is a species of grass in the oat genus. It is known as the common wild oat. This oat is native to Eurasia but it has been introduced to most of the other temperate regions of the world. It is naturalized in some areas and considered a noxious weed in others...
and Avena barbata
Avena barbata
Avena barbata is a species of wild oat known by the common name slender wild oat. It has edible seeds. It is native to central Asia and the Mediterranean Basin. It is also known in North America as an introduced species and noxious weed. It is widespread in California, where it has displaced native...
). However much of the grassland has been replaced by various oaks, especially Coast Live Oak
Coast Live Oak
Quercus agrifolia, the Coast Live Oak, is an evergreen oak , native to the California Floristic Province. It grows west of the Sierra Nevada from Mendocino County, California, south to northern Baja California in Mexico. It is classified in the red oak section Quercus agrifolia, the Coast Live Oak,...
(Quercus agrifolia), and Pacific Madrone
Pacific Madrone
Arbutus menziesii, commonly known as the Pacific Madrone, is a species of Arbutus found on the west coast of North America, from British Columbia to California...
(Arbutus menziesii). More recently, the oak/madrone forest is being succeeded
Ecological succession
Ecological succession, is the phenomenon or process by which a community progressively transforms itself until a stable community is formed. It is a fundamental concept in ecology, and refers to more or less predictable and orderly changes in the composition or structure of an ecological community...
by specimens of large Douglas fir (Pseudotsuga menziesii) as in the image above. In addition there are several groves of second growth Coast Redwoods (Sequoia sempervirens) in the preserve, some in large "fairy rings" indicating that trees of immense girth were cut down in the nineteenth century.
Academic studies
Numerous academic studies and ecological experiments are conducted at Jasper Ridge.Global change experiment
The Global Change Experiment studies the response of California annual grassland to global change, including elevated atmospheric CO2, temperature, altered precipitation, and increased nitrogen deposition.Argentine ant invasion
This project studies and tracks the Argentine antArgentine ant
The Argentine ant, Linepithema humile, is a dark ant native to northern Argentina, Uruguay, Paraguay, and southern Brazil...
s, an invasive species.