San Joaquin Experimental Range
Location
37.1, -119.716667
San Joaquin Experimental Range Research Natural Area
This established RNA is on the San Joaquin Experimental Range, near the town of O’Neals, Madera County, approximately 28 miles (45 km) north of Fresno. It is within the E1/2 of section 6 T10S, R21E MDM (37°06'N., 119°43'W.), USGS Millerton Lake West quad. Ecological subsection – Lower Granitic Foothills (M261Fc).
Target element: blue oak – foothill pine (Quercus douglasii – Pinus sabiniana)
Ecological and Physical Description
The area covers 70 acres (28 ha). Its topography consists of rolling hills with gentle slopes. Elevations range from 1065 to 1200 ft (325-366 m).
Distinctive Features
The blue oak-foothill pine woodland (71410) is representative of the vegetation type typical of most of the granitic foothills on the east side of the San Joaquin Valley from Madera County southward. This RNA has been maintained as a research area since 1934 and has been associated with research studies on the Experimental Range since that date. From 1935 to 1965, 192 publications relating to research done on the Experimental Range were released. The Range scientists maintain a zoological collection as well as an herbarium. Basic weather data have been collected since 1934. The RNA provides opportunities for studying the impact of livestock grazing and fire on annual plants. Permanent photo stations and vegetation sampling transects (installed in 1992) exist at the Range.
Association Types
Foothill Pine-Oak Woodland (71410) and Non-Native Grassland (42200): Vegetation cover of the RNA is open woodland (foothill pine, blue oak, and Quercus wislizenii) with shrub and annual plant understory. Ceanothus cuneatus, Arctostaphylos mariposa, Bromus mollis, B. rigidus, Festuca megalura, and Erodium botrys are among the more important nontree species. There is no map of vegetation cover.
Grazing History
In the late 1800s, domestic livestock grazed the area heavily. The RNA has not been grazed since 1934.
Plant Diversity
Three hundred and nineteen species are identified for the whole San Joaquin Experimental Range. There is no specific plant list for the RNA.
Mean annual precipitation is 19 inches (4835 mm), and mean monthly temperatures vary between 41.9 and 80.4 °F (5.5-26.9 °C).
The soil is mostly Ahwahnee coarse sandy loam with small inclusions of Hanford coarse sandy loam and Visalia coarse sandy loam.
The last fire occurred in the area around 1929.
Publications
- Sheauchi Cheng. 2004. San Joaquin Experimental Range
- Sheauchi Cheng. 2004. Forest Service Research Natural Areas in California