The Diablo Range is a mountain range in the California Coast Ranges subdivision of the Pacific Coast Ranges in northern California, United States. It stretches from the eastern San Francisco Bay Area at its northern end to the Salinas Valley area at its southern end.
| Diablo Range | |
|---|---|
 Mount Hamilton | |
| Highest point | |
| Elevation | 5,240 ft (1,600 m) |
| Dimensions | |
| Length | 180 mi (290 km) north-south from Carquinez Strait to Polonio Pass |
| Width | 20 mi (32 km) |
| Geography | |
  Diablo Range Location of the Diablo Mountain Range in California, U.S. | |
| Country | United States |
| State | California |
| Region | Central California |
| Range coordinates | 36°22′10.844″N 120°38′39.609″W / 36.36967889°N 120.64433583°W |
| Topo map | USGS San Benito Mountain |
Geography
The Diablo Range extends from the Carquinez Strait in the north to Orchard Peak and Polonio Pass in the south, near the point where State Route 46 crosses over the Coast Ranges at Cholame, as described by the United States Geological Survey (USGS). It is bordered on the northeast by the San Joaquin River, on the southeast by the San Joaquin Valley, on the southwest by the Salinas River, and on the northwest by the Santa Clara Valley and San Francisco Bay. On USGS maps, the "Diablo Range" is shown as the ridgeline which runs between its namesake Mount Diablo southeastward past Mount Hamilton. However, the USGS Geographic Names Information System (GNIS) includes the East Bay Hills in its list of various GPS coordinates for the Diablo Range. Although not formally recognized by USGS GNIS, the East Bay Hills consists of the Briones Hills furthest north, then the Berkeley Hills, the San Leandro Hills centrally, and Walpert Ridge and Pleasanton Ridge to the southwest and southeast, culminating at Alameda Creek/Highway 84.
Geologically, the Diablo Range corresponds to the California Coast Ranges east of the Calaveras Fault in its northern section. For much of its length, it is paralleled by other sections of the California Coast Ranges to the west, the Santa Cruz Mountains across the southern San Francisco Bay and Santa Clara Valley, and the Santa Lucia Range across the Salinas Valley. The East Bay Hills are bounded geologically by the Calaveras Fault to the east and the Hayward Fault to the west.
The range passes through Contra Costa, Alameda, San Joaquin, Santa Clara, Stanislaus, Merced, San Benito, Fresno, Monterey, and Kings Counties, and ends in the northwesternmost extremity of Kern County.
Topography
Though the average elevation is about 3,000 feet (910 meters), a summit of over 2,300 feet (700 m) is considered high, mainly because the range is mostly rolling grassland and plateaus, punctuated by isolated peaks. Plateaus are usually at about 2,000–3,000 feet (610–910 m). Hills rise to about 1,000 feet (300 m), while foothills such those in the Santa Clara Valley, Livermore Valley and San Joaquin Valley are typically 400–1,000 feet (120–300 m).
Canyons are usually 300–400 feet (91–122 m) deep; valleys are often deeper but less steep-sided. Peaks often have high topographic prominence, as they are surrounded by valleys or lower hills or plateaus. Streams draining the eastern slopes of the Diablo Range include Hospital Creek and Ingram Creek. Stream draining the western slopes include Alameda Creek and Coyote Creek.
Peaks
The Diablo Range's peaks and ridges are between 2,517–5,241 feet (767–1,597 m) and are distinct landmarks. Mount Diablo (3,849 feet (1,173 m)), San Benito Mountain (5,241 feet (1,597 m)), Mount Hamilton Ridge (4,230–4,260 feet (1,290–1,300 m)), and Mount Stakes (3,804 feet (1,159 m)) are four of the highest peaks in the range.
Human elements
The Diablo Range is paralleled for much of its distance by U.S. Route 101 to the west and by I-5 to the east. Major routes of travel through the range include:
- North of the range
- BNSF Railway/Amtrak San Joaquin
- Willow Pass
- State Route 4
- BART Yellow Line
- Altamont Pass
- Union Pacific Railroad/Altamont Corridor Express
- I-580
- Sunol Valley
- State Route 84
- I-680
- Patterson Pass
- Corral Hollow Pass
- Mount Hamilton
- State Route 130
- Pacheco Pass
- State Route 152
- Future California High-Speed Rail
- Panoche Pass
- State Route 198
- Cottonwood Pass (State Route 41)
- Polonio Pass (State Route 46)
A sparsely used gravel road is the highest road in the range, with its highest point being on San Benito Mountain at over 5,000 feet.[citation needed]
The Diablo Range is largely unpopulated outside of the San Francisco Bay Area. Major nearby communities include, Antioch, Pittsburg, Concord, Walnut Creek, Alamo, Danville, San Ramon, Pleasanton, Livermore, Fremont, Milpitas, San Jose, Morgan Hill, and Gilroy and the Central Valley city of Tracy. South of Pacheco Pass, the only major nearby communities (those with a population over 15,000) are Los Banos, and Hollister. The small town of Coalinga may also be notable for its location on State Route 198, one of the few routes through the mountains. Also the town of Kettleman City is also on State Route 41, another route that crosses the mountains. Towns west of the range south of Gilroy include: Salinas, King City, and Paso Robles.
Protected areas
Most of the range consists of private ranchland, limiting recreational use. However, the range does contain several areas of parkland, including Mount Diablo State Park, Alum Rock Park, Grant Ranch Park, Henry W. Coe State Park, Laguna Mountain Recreation Area, and the BLM's Clear Creek Management Area. In addition, some private land is held in conservation easements by the California Rangeland Trust.
Natural history
Since the range lies around 10–50 miles (16–80 kilometers) inland from the ocean, and other coastal ranges like the Santa Lucia Range and the Santa Cruz Mountains block incoming moisture, the range gets little precipitation. In addition, the average elevation of 3,000 feet (910 m) is not high enough to catch most of the incoming moisture at higher altitudes.
Winters are mild with moderate rainfall, but summers are very dry and hot. Areas above 2,500 feet (762 m) get light to moderate snow in the winter, especially at the highest point, the 5,241 ft (1,597 m) San Benito Mountain in the remote southeastern section of the range. However, though sites at the lower end get annual snowfall, it is typically light and melts too fast to be noticed. Once or twice a decade there is seriously deep and long lasting snowfall.
Mercury contamination near the southern end of the range is an ongoing problem, due to the New Idria quicksilver mines, which stopped production in the 1970s. Heavy mercury contamination has been documented in the San Carlos and Silver Creeks, which flow into Panoche Creek, and thence into the San Joaquin River. This has resulted in mercury contamination all the way downstream to the San Francisco Bay. Silver and San Carlos creeks provide a wetland environment in an otherwise arid region and are important for the ecology of the region. As of 2011, New Idria has been listed as a Superfund site and scheduled for cleanup.
Flora
The Diablo Range is part of the California interior chaparral and woodlands ecoregion. It is covered mostly by chaparral and California oak woodland communities, with stands of closed-cone pine forests appearing above 4,000 feet (1,219 m). The native bunch grass savanna has been predominantly replaced by annual Mediterranean grasses, except in some rare habitat fragments. The understory is dominated with nonnative invasives. Blooming in spring are such plants as Viola pedunculata, Dodecatheon pulchellum, Fritillaria liliacea, and Ribes malvaceum, which can be viewed in the Blue Oak Ranch Reserve.
The range's riparian zones have such trees as bigleaf maple (Acer macrophyllum), white alder (Alnus rhombifolia), California bay (Umbellularia californica), and California sycamore (Platanus racemosa).
The most common trees are coast live oak (Quercus agrifolia) and blue oak (Quercus douglasii), with the largest blue oak growing in Alameda County. There are also good populations of California buckeye (Aesculus californica), and California black oak (Quercus kelloggii). The gray pine (Pinus sabiniana) and rarer Coulter pine (Pinus coulteri) can be found at all elevations, especially between 800–3,000 feet (240–910 m). Coulter pine reaches its northern limit on northern of Mt. Diablo. The conifers at higher elevations in the Diablo Range include knobcone pine (Pinus attenuata), Jeffrey pine (Pinus jeffreyi) and ponderosa pine (Pinus ponderosa).
Fauna
The Diablo Range attracts far more raptors than coastal forests, such as red-tailed hawks. Golden eagle nesting sites are found in the Diablo Range, reaching their highest density in southern Alameda County.
The Bay checkerspot butterfly, a federally listed threatened species, has habitat in the Range, especially at Mount Diablo. The California tiger salamander (Ambystoma californiense), also a federally threatened species and a vulnerable species of amphibian native to Northern California, lives in ponds in the range. The northern Pacific rattlesnake is thriving, as are many ground squirrels, hares, and various species of native and nonnative rodents.
Tule elk (Cervus canadensis ssp. nannodes) were restored to Mount Hamilton between 1978–1981 and are slowly recovering in several small herds in Santa Clara and Alameda Counties. See Mount Hamilton elk recovery. Black-tailed deer are abundant. Pronghorn, grizzly bears, and wolves were extirpated in the 1800s. There still are numerous coyotes and some of the more vital mountain lion populations in the state. There are excellent populations of bobcats and gray foxes, which depend on the chaparral habitat.
A species of millipede, Illacme plenipes, is endemic to the southern Diablo Range. First described in 1926, then not seen again until 2005, the species has more legs than any other species of millipede, with one specimen having 750.
See also
![image]()
Media from Commons![image]()
Travel information from Wikivoyage
- Mountain ranges of the San Francisco Bay Area
- Rancho Cañada de Pala
- Rancho Santa Teresa
References
- "Diablo Range". Geographic Names Information System. United States Geological Survey, United States Department of the Interior. Retrieved 2009-05-03.
- "Briones Hills". Geographic Names Information System. United States Geological Survey, United States Department of the Interior.
- "Berkeley Hills". Geographic Names Information System. United States Geological Survey, United States Department of the Interior.
- "San Leandro Hills". Geographic Names Information System. United States Geological Survey, United States Department of the Interior.
- "Walpert Ridge". Geographic Names Information System. United States Geological Survey, United States Department of the Interior.
- "Pleasanton Ridge". Geographic Names Information System. United States Geological Survey, United States Department of the Interior.
- R. C. Crane (1995). "Geology of Mount Diablo Region and East Bay Hills". In E. M. Sangines; D. W. Andersen; A. B. Buising (eds.). Recent Geologic Studies in the San Francisco Bay Area. Vol. 76. Pacific Section, Society for Sedimentary Geology (S.E.P.M.). pp. 87–114. Retrieved July 3, 2024.
- EPA,OSWER,OSRTI, US (4 September 2015). "Search for Superfund Sites Where You Live - US EPA". US EPA. Retrieved 16 April 2018.
{{cite web}}: CS1 maint: multiple names: authors list (link) - http://www.blueoakranchreserve.org/BORR/Galleries/Galleries.html Archived 2011-07-25 at the Wayback Machine . accessed 6/28/2010
- http://www.blueoakranchreserve.org/BORR/Galleries/Pages/Habitat_Highlights%3A_The_Arroyo_Hondo_Survey.html Archived 2011-07-25 at the Wayback Machine . accessed 6/28/2010
- C. Michael Hogan, Paul Hoffey et al. al., Environmental Impact Report for the Aiassa Site off Mount Hamilton Road, Santa Clara County, Ca., Santa Clara County Document EMI 7364W1 SCH88071916, August, 1989
- Peterson, Hans- Raptors of California
- Fatal Attraction: Birds and Wind Turbines | QUEST Archived 2010-12-11 at the Wayback Machine. Kqed.org (2007-06-26). Retrieved on 2013-07-21.
- Cool Critters: The Golden Eagle | QUEST Archived 2011-06-17 at the Wayback Machine. Kqed.org (2009-07-28). Retrieved on 2013-07-21.
- http://www.blueoakranchreserve.org/BORR/Galleries/Pages/Species_Highlights%3A_The_California_Tiger_Salamander.html Archived 2011-07-25 at the Wayback Machine . accessed 6/28/2010
- 666-Legged Creature Rediscovered. LiveScience (2006-06-07). Retrieved on 2013-07-21.
The Diablo Range is a mountain range in the California Coast Ranges subdivision of the Pacific Coast Ranges in northern California United States It stretches from the eastern San Francisco Bay Area at its northern end to the Salinas Valley area at its southern end Diablo RangeMount HamiltonHighest pointElevation5 240 ft 1 600 m DimensionsLength180 mi 290 km north south from Carquinez Strait to Polonio PassWidth20 mi 32 km GeographyDiablo RangeLocation of the Diablo Mountain Range in California U S CountryUnited StatesStateCaliforniaRegionCentral CaliforniaRange coordinates36 22 10 844 N 120 38 39 609 W 36 36967889 N 120 64433583 W 36 36967889 120 64433583Topo mapUSGS San Benito MountainGeographyThe Diablo Range extends from the Carquinez Strait in the north to Orchard Peak and Polonio Pass in the south near the point where State Route 46 crosses over the Coast Ranges at Cholame as described by the United States Geological Survey USGS It is bordered on the northeast by the San Joaquin River on the southeast by the San Joaquin Valley on the southwest by the Salinas River and on the northwest by the Santa Clara Valley and San Francisco Bay On USGS maps the Diablo Range is shown as the ridgeline which runs between its namesake Mount Diablo southeastward past Mount Hamilton However the USGS Geographic Names Information System GNIS includes the East Bay Hills in its list of various GPS coordinates for the Diablo Range Although not formally recognized by USGS GNIS the East Bay Hills consists of the Briones Hills furthest north then the Berkeley Hills the San Leandro Hills centrally and Walpert Ridge and Pleasanton Ridge to the southwest and southeast culminating at Alameda Creek Highway 84 Geologically the Diablo Range corresponds to the California Coast Ranges east of the Calaveras Fault in its northern section For much of its length it is paralleled by other sections of the California Coast Ranges to the west the Santa Cruz Mountains across the southern San Francisco Bay and Santa Clara Valley and the Santa Lucia Range across the Salinas Valley The East Bay Hills are bounded geologically by the Calaveras Fault to the east and the Hayward Fault to the west The range passes through Contra Costa Alameda San Joaquin Santa Clara Stanislaus Merced San Benito Fresno Monterey and Kings Counties and ends in the northwesternmost extremity of Kern County Topography Though the average elevation is about 3 000 feet 910 meters a summit of over 2 300 feet 700 m is considered high mainly because the range is mostly rolling grassland and plateaus punctuated by isolated peaks Plateaus are usually at about 2 000 3 000 feet 610 910 m Hills rise to about 1 000 feet 300 m while foothills such those in the Santa Clara Valley Livermore Valley and San Joaquin Valley are typically 400 1 000 feet 120 300 m Canyons are usually 300 400 feet 91 122 m deep valleys are often deeper but less steep sided Peaks often have high topographic prominence as they are surrounded by valleys or lower hills or plateaus Streams draining the eastern slopes of the Diablo Range include Hospital Creek and Ingram Creek Stream draining the western slopes include Alameda Creek and Coyote Creek Peaks The Diablo Range s peaks and ridges are between 2 517 5 241 feet 767 1 597 m and are distinct landmarks Mount Diablo 3 849 feet 1 173 m San Benito Mountain 5 241 feet 1 597 m Mount Hamilton Ridge 4 230 4 260 feet 1 290 1 300 m and Mount Stakes 3 804 feet 1 159 m are four of the highest peaks in the range View of Mt Diablo from Concord Main peak at right North Peak at left Mt Zion at center scroll image L R to view Human elementsThe south edge mostly Monument Peak of the Mission Ridge as seen from Milpitas The Diablo Range is paralleled for much of its distance by U S Route 101 to the west and by I 5 to the east Major routes of travel through the range include North of the range BNSF Railway Amtrak San Joaquin Willow Pass State Route 4 BART Yellow Line Altamont Pass Union Pacific Railroad Altamont Corridor Express I 580 Sunol Valley State Route 84 I 680 Patterson Pass Corral Hollow Pass Mount Hamilton State Route 130 Pacheco Pass State Route 152 Future California High Speed Rail Panoche Pass State Route 198 Cottonwood Pass State Route 41 Polonio Pass State Route 46 A sparsely used gravel road is the highest road in the range with its highest point being on San Benito Mountain at over 5 000 feet citation needed The Diablo Range is largely unpopulated outside of the San Francisco Bay Area Major nearby communities include Antioch Pittsburg Concord Walnut Creek Alamo Danville San Ramon Pleasanton Livermore Fremont Milpitas San Jose Morgan Hill and Gilroy and the Central Valley city of Tracy South of Pacheco Pass the only major nearby communities those with a population over 15 000 are Los Banos and Hollister The small town of Coalinga may also be notable for its location on State Route 198 one of the few routes through the mountains Also the town of Kettleman City is also on State Route 41 another route that crosses the mountains Towns west of the range south of Gilroy include Salinas King City and Paso Robles The southern end of Henry W Coe State Park near GilroyProtected areas Most of the range consists of private ranchland limiting recreational use However the range does contain several areas of parkland including Mount Diablo State Park Alum Rock Park Grant Ranch Park Henry W Coe State Park Laguna Mountain Recreation Area and the BLM s Clear Creek Management Area In addition some private land is held in conservation easements by the California Rangeland Trust Natural historySince the range lies around 10 50 miles 16 80 kilometers inland from the ocean and other coastal ranges like the Santa Lucia Range and the Santa Cruz Mountains block incoming moisture the range gets little precipitation In addition the average elevation of 3 000 feet 910 m is not high enough to catch most of the incoming moisture at higher altitudes Winters are mild with moderate rainfall but summers are very dry and hot Areas above 2 500 feet 762 m get light to moderate snow in the winter especially at the highest point the 5 241 ft 1 597 m San Benito Mountain in the remote southeastern section of the range However though sites at the lower end get annual snowfall it is typically light and melts too fast to be noticed Once or twice a decade there is seriously deep and long lasting snowfall Mercury contamination near the southern end of the range is an ongoing problem due to the New Idria quicksilver mines which stopped production in the 1970s Heavy mercury contamination has been documented in the San Carlos and Silver Creeks which flow into Panoche Creek and thence into the San Joaquin River This has resulted in mercury contamination all the way downstream to the San Francisco Bay Silver and San Carlos creeks provide a wetland environment in an otherwise arid region and are important for the ecology of the region As of 2011 New Idria has been listed as a Superfund site and scheduled for cleanup Flora The Diablo Range is part of the California interior chaparral and woodlands ecoregion It is covered mostly by chaparral and California oak woodland communities with stands of closed cone pine forests appearing above 4 000 feet 1 219 m The native bunch grass savanna has been predominantly replaced by annual Mediterranean grasses except in some rare habitat fragments The understory is dominated with nonnative invasives Blooming in spring are such plants as Viola pedunculata Dodecatheon pulchellum Fritillaria liliacea and Ribes malvaceum which can be viewed in the Blue Oak Ranch Reserve The range s riparian zones have such trees as bigleaf maple Acer macrophyllum white alder Alnus rhombifolia California bay Umbellularia californica and California sycamore Platanus racemosa The most common trees are coast live oak Quercus agrifolia and blue oak Quercus douglasii with the largest blue oak growing in Alameda County There are also good populations of California buckeye Aesculus californica and California black oak Quercus kelloggii The gray pine Pinus sabiniana and rarer Coulter pine Pinus coulteri can be found at all elevations especially between 800 3 000 feet 240 910 m Coulter pine reaches its northern limit on northern of Mt Diablo The conifers at higher elevations in the Diablo Range include knobcone pine Pinus attenuata Jeffrey pine Pinus jeffreyi and ponderosa pine Pinus ponderosa Fauna Three tule elk in Basking Ridge Park just north of U S Highway 101 which is a barrier to elk migration to the Coast Range The Diablo Range attracts far more raptors than coastal forests such as red tailed hawks Golden eagle nesting sites are found in the Diablo Range reaching their highest density in southern Alameda County The Bay checkerspot butterfly a federally listed threatened species has habitat in the Range especially at Mount Diablo The California tiger salamander Ambystoma californiense also a federally threatened species and a vulnerable species of amphibian native to Northern California lives in ponds in the range The northern Pacific rattlesnake is thriving as are many ground squirrels hares and various species of native and nonnative rodents Tule elk Cervus canadensis ssp nannodes were restored to Mount Hamilton between 1978 1981 and are slowly recovering in several small herds in Santa Clara and Alameda Counties See Mount Hamilton elk recovery Black tailed deer are abundant Pronghorn grizzly bears and wolves were extirpated in the 1800s There still are numerous coyotes and some of the more vital mountain lion populations in the state There are excellent populations of bobcats and gray foxes which depend on the chaparral habitat A species of millipede Illacme plenipes is endemic to the southern Diablo Range First described in 1926 then not seen again until 2005 the species has more legs than any other species of millipede with one specimen having 750 See alsoDiablo Range at Wikipedia s sister projects Media from CommonsTravel information from Wikivoyage Mountain ranges of the San Francisco Bay Area Rancho Canada de Pala Rancho Santa TeresaReferences Diablo Range Geographic Names Information System United States Geological Survey United States Department of the Interior Retrieved 2009 05 03 Briones Hills Geographic Names Information System United States Geological Survey United States Department of the Interior Berkeley Hills Geographic Names Information System United States Geological Survey United States Department of the Interior San Leandro Hills Geographic Names Information System United States Geological Survey United States Department of the Interior Walpert Ridge Geographic Names Information System United States Geological Survey United States Department of the Interior Pleasanton Ridge Geographic Names Information System United States Geological Survey United States Department of the Interior R C Crane 1995 Geology of Mount Diablo Region and East Bay Hills In E M Sangines D W Andersen A B Buising eds Recent Geologic Studies in the San Francisco Bay Area Vol 76 Pacific Section Society for Sedimentary Geology S E P M pp 87 114 Retrieved July 3 2024 EPA OSWER OSRTI US 4 September 2015 Search for Superfund Sites Where You Live US EPA US EPA Retrieved 16 April 2018 a href wiki Template Cite web title Template Cite web cite web a CS1 maint multiple names authors list link http www blueoakranchreserve org BORR Galleries Galleries html Archived 2011 07 25 at the Wayback Machine accessed 6 28 2010 http www blueoakranchreserve org BORR Galleries Pages Habitat Highlights 3A The Arroyo Hondo Survey html Archived 2011 07 25 at the Wayback Machine accessed 6 28 2010 C Michael Hogan Paul Hoffey et al al Environmental Impact Report for the Aiassa Site off Mount Hamilton Road Santa Clara County Ca Santa Clara County Document EMI 7364W1 SCH88071916 August 1989 Peterson Hans Raptors of California Fatal Attraction Birds and Wind Turbines QUEST Archived 2010 12 11 at the Wayback Machine Kqed org 2007 06 26 Retrieved on 2013 07 21 Cool Critters The Golden Eagle QUEST Archived 2011 06 17 at the Wayback Machine Kqed org 2009 07 28 Retrieved on 2013 07 21 http www blueoakranchreserve org BORR Galleries Pages Species Highlights 3A The California Tiger Salamander html Archived 2011 07 25 at the Wayback Machine accessed 6 28 2010 666 Legged Creature Rediscovered LiveScience 2006 06 07 Retrieved on 2013 07 21
