A Proclamation on Expanding the San Gabriel Mountains National Monument, 2024
Through Proclamation 9194 of October 10, 2014, President Obama established the San Gabriel Mountains National Monument (monument) to protect the rich cultural history, striking geologic features, and vibrant ecological diversity contained within a portion of the Angeles National Forest. Situated in the mountains north of Los Angeles, the monument is a verdant oasis that contains abundant and distinctive flora and fauna; unique geology; and evidence of centuries of occupation and use by Tribal Nations and Indigenous peoples, Spanish missionaries and colonists, Mexican rancheros, and Euro-American settlers and prospectors. In addition to protecting these and other objects of historic and scientific interest, the monument’s pristine natural lands and proximity to Los Angeles make it a unique place of rejuvenation and recreation for the people of the ever-changing urban and suburban communities of greater Los Angeles.
Expanding the monument to include the expanse of the Angeles National Forest that stretches south and west from the current boundary to the National Forest boundary near foothill communities of Los Angeles will protect additional objects of scientific and historic interest. This expansion area contains evidence of thousands of years of use and occupation by Indigenous peoples, as well as evidence of more recent human uses, including the ruins of grand recreation resorts and of a missile unit built during the Cold War. A diversity of animals, birds, reptiles, and other wildlife, including numerous threatened and endangered species, live among the unique geological and ecological features of the expansion area, including its unusual canyons, chaparral, and coastal sage scrub lands, and use the area to travel from the lowlands in the south to the soaring mountains in the north.
Since time immemorial, the rich landscape within the expansion area has sustained a mosaic of Indigenous peoples, including the people known as the Gabrielino, Kizh, or Tongva, and the Chumash Kitanemuk, Serrano, and Tataviam peoples. The displacement of these peoples from the area began between 1770 and 1816, when Spanish missionaries forcibly assimilated the region’s Indigenous families into surrounding missions, and continued past California’s admission into the Union. Today, their descendants are part of Tribal Nations and other Indigenous peoples in the region, some of whose members continue to use the area for ceremonial purposes, as well as for collecting traditional plants important for basketry, food, and medicine.
Evidence of many eras of human history can be found in the expansion area. Dozens of known sites shed light on the daily life and activities of Indigenous peoples, including seasonal habitation, plant and mineral resource collection, food processing, tool manufacturing, and transportation corridors. One known site contains a seasonal encampment where there is evidence of food processing and tool production use from 1150 to 1771, including midden, flaked lithics and tools, ground stones, and hearths and earth ovens. The area also contains evidence of use associated with permanent Indigenous villages that were located adjacent to the expansion area at the base of the area’s canyons, including the Tongva villages of Muuhonga and Tohuunga.
Other sites contain lithic materials, including fused shale and obsidian that came from areas far to the north. These materials provide evidence of the ancient Indigenous trade routes that crisscrossed the area, bringing small game, deer, acorns, sage, piñon nuts, yucca, elderberry, and manzanita berry, among other resources, south into the Los Angeles Basin, and asphaltum, shell and soapstone cooking vessels, beads, pipes, effigies, pendants, and comals north into the mountains.
Mining made its way to the San Gabriel Mountains in the 19th century, following the discovery of gold in Placerita Canyon in 1842. Visitors to the area today can still see evidence of this first gold rush, including the remains of a mine shaft and ore cart rails of the Dawn Mine and mill site, which remained in operation until 1954. The remains of the Tujunga Mining District, including the shafts of the Josephine Mine above Mill Creek, evidence a second minor gold rush in the late 1880s.
The expansion area also contains evidence of Euro-American settlers who looked to these lands to provide mineral resources, wood for fuel and construction, other building materials, and water. Near Little Tujunga Canyon, three well-preserved limekilns, eligible for inclusion in the National Register of Historic Places, were constructed around 1870 with local limestone and granite cobbles within a mortar matrix. Visitors to the area can also traverse trails first developed by Indigenous peoples and later modified by Euro-American settlers. For example, ranchero and later Mayor of Los Angeles Benjamin Davis Wilson, also known as Don Benito, using labor from Indigenous and Spanish workers, built the trail known today as the Mount Wilson Trail to transport timber to his rancho. The Gabrielino Trail, which the Congress designated as America’s first National Recreation Trail in 1970, incorporates trails that another 19th century trail maker, Wilbur Sturtevant, developed possibly along established Indigenous routes.
The expansion area also contains evidence of highly popular recreational pursuits of the Great Hiking Era of the early 20th century, when throngs of hikers and outdoor enthusiasts went to the mountains of southern California. This evidence includes the remains of the Mount Lowe Electric Railway (Railway), which was opened in 1893 to transport passengers from foothill communities to three impressive mountain resorts. The Railway, which is listed in the National Register of Historic Places as a Historic District, was the only scenic mountain electric traction railway ever built in the United States and became a tourist destination because of its remarkable location and engineering audacity. It recorded an estimated three million visitors between 1893 and 1938.
Today’s visitors who hike to Echo Mountain will see portions of the railroad bed and crossties, a platform, trestle foundations, and scattered remains of the powerhouse’s massive cog-wheel or “bullwheel” used to pull the incline car up the mountain. Nearby, visitors can also observe the remains of a once grand resort served by the Railway, including a staircase and the foundation footprint of a 70-room hotel, the remains of a zoo, the foundation of an observatory and telescope pedestal, two large concrete water tanks, and rock retaining walls outlining the tennis courts and casino. Visitors can also see remnants of a three million candlepower searchlight installed on the mountain from the 1893 Columbia Exposition World’s Fair, and a largely intact, original “echophone” used by visitors to hear the canyon’s echoes. A trestle abutment of the Railway can also be found near the Mount Lowe Campground. Nearby, at the head of Grand Canyon, visitors can see the rear wall of another of the resorts served by the Railway, the 12-room Swiss-style Ye Alpine Tavern.
To the north and west of the Railway, ruins of hike-in camps include the foundation of Switzer’s Camp, developed by Commodore Perry Switzer in the early 1880s. That camp hosted Henry Ford, Shirley Temple, and numerous other celebrities.
The southeastern portion of the expansion area contains 64 cabins that were once part of the Big Santa Anita Canyon Summer Home Tract. This development was established to respond to the burgeoning early 20th century desire to be closer to, and have second homes in, natural settings. The tract originally contained 88 cabins and 12 associated campgrounds. Eligible for inclusion in the National Register of Historic Places, the cabins epitomized the rustic architectural design style of the early 20th century, and are notable for the care taken in sensitively siting them into the rugged topography.
Above El Prieto Canyon, in the southern portion of the expansion area, is the homestead site of a former cabin built and lived in by Robert Owens. Owens was a formerly enslaved person who built a thriving wood and building supply business in and around the canyon, becoming the wealthiest African American in Los Angeles County in 1865.
The expansion area also includes the historic Big Tujunga Dam, completed in 1931, and Brown Mountain Dam, constructed by the United States Forest Service (Forest Service) in 1943. The Lincoln Avenue Water Company water system is also in the area, which was constructed in the 1880s and is eligible for inclusion in the National Register of Historic Places.
The Los Pinetos Nike Missile site, which is eligible for inclusion in the National Register of Historic Places, played a vital role in United States national defense during the Cold War era. This site, along with the Mount Gleason Nike Missile site, which was destroyed by a wildfire in 2009, is among the 300 Nike Missile sites constructed across the country from 1955 to 1958 that were intended to serve as the last line of defense against Soviet bomber planes. The Los Pinetos Nike Missile site is unusual because its launch, administrative, and battery control facilities are located within a single line of sight.
In addition to extensive historical resources, the expansion area reflects massive geologic forces over hundreds of millions of years that created an exceptional landscape, providing views deep into the ancient Earth. The steep and rugged San Gabriel Mountains are one of the fastest growing mountain ranges in the world. These mountains form a major part of the east-west trending Transverse Ranges of southern California, a portion of which is in the expansion area. They were formed from eons of geological movement during the Mesozoic and Cenozoic Eras when the geologic Farallon Plate and the North American Plate crashed together. Dragged as much as 50 degrees in some places by these powerful forces, the San Gabriel Mountains have an unusual east-west orientation, instead of the more typical north-south orientation.
Around Mount Lowe, the uplift of rare anorthosite complex rocks that are 1.2 billion years old, including anorthosite pluton, syenite, and mafic rocks, reveals the dramatic twisting that can occur as mountains are formed. Evidence of this geological process typically lies far below the surface, making the area a hotbed of geological study and a natural classroom for the public. Around Mendenhall Peak, the bands and swirls of 1.7 to 1.8 billion-year-old Mendenhall Gneiss, the region’s oldest rocks, are exposed.
The expansion area also contains scientifically important paleontological resources, particularly invertebrate fossils such as oysters and gastropods, at sites including Gold Canyon near Little Tujunga Canyon.
The expansion area is composed of many distinct and diverse ecosystem zones that support rich biodiversity, including more than 500 native plants and fungi, as well as important habitat including riparian woodlands, montane hardwood and conifer forests, coastal sage scrub, alluvial sage scrub, and extensive chaparral. The area also provides important connectivity to enable species to move from the foothills of the south to the soaring mountains of the north.
Perennial streams, springs, and associated riparian areas, and numerous seasonal tributaries, all support wetland-dependent plant species such as the California muhly and the Sonoran maiden fern, the latter of which is designated as rare by the State of California. These riparian areas also provide critical habitat for sensitive fish and amphibians, including the threatened Santa Ana speckled dace and the threatened Santa Ana sucker found in Big Tujunga Creek, and the endangered Arroyo Toad found in both the Arroyo Seco and Big Tujunga Creek. Habitats for the steelhead trout and the Arroyo chub, a State species of special concern, are also found in Arroyo Seco and Big Tujunga Creek.
A rich variety of rare plants can be found in the expansion area, including the San Gabriel manzanita, San Gabriel Mountains leather oak, San Gabriel Mountains sunflower, San Gabriel bedstraw, and San Gabriel Mountains dudleya, all of which are found only or primarily in the San Gabriel Mountains, and the California muhly, fragrant pitcher sage, Greata’s aster, and Plummer’s mariposa lily, found only in southern California. Other rare species include the Mount Gleason paintbrush, California satintail, and Chaparral yucca, which is part of an extraordinary, mutually beneficial partnership with the interdependent California yucca moth.
While extremely reduced from its overall historic range, pockets of alluvial scrub habitat, particularly around Big Tujunga Canyon, provide a home for the rare endemic Davidson’s bushmallow. Southern California’s bigcone Douglas-fir, which is well adapted to the region’s natural wildfire regime, is present in strongholds around San Gabriel Peak, the Switzer Falls Trail, and south of Mount Wilson, providing important nesting and roosting habitat for the California spotted owl, which the United States Fish and Wildlife Service has proposed to list as endangered.
Coastal sage scrub, among the most threatened plant communities in California, occurs primarily at elevations below 2,500 feet south of Mount Wilson and along the north side of Big Tujunga Creek. This rare plant community includes California sagebrush, brittlebush, California buckwheat, and various types of sage. Coastal sage scrub, which can be found in Placerita Canyon, provides critical habitat for the threatened coastal California gnatcatcher.
Montane hardwood and conifer forests south of Big Tujunga Bridge and Mount Wilson are typified by live oak, bigleaf maple, California bay, incense cedar, Pacific madrone, Coulter pine, sugar pine, and California incense cedar, as well as understory species such as ceanothus, coffeeberry, gooseberry, and currants. These forests provide habitat for a wide variety of wildlife such as black bears, mule deer, various reptiles, birds, and butterflies, as well as fish and amphibians that rely on the cool water found there. Birds that can be found seasonally or year-round in the expansion area include the endangered California condor and Least Bell’s vireo; the threatened western population of yellow-billed cuckoo; the Swainson’s hawk, which is listed as threatened by the State of California; the Peregrine falcon; and the California-listed willow flycatcher. The southwestern pond turtle, which the United States Fish and Wildlife Service has proposed to list as threatened, is also found in the area, along with the two-striped garter snake and the Southern California legless lizard, which are designated as sensitive species by the Angeles National Forest. Many species of bats use the area’s canyons and waters, including the pallid bat and big free-tailed bat, both California special status species, along with migrants and resident bats, such as the hoary bat, Yuma myotis, small-footed myotis, canyon bat, big brown bat, Mexican free-tailed bat, long-eared myotis, and California myotis.
In addition to these key habitats, the area also contains important migration corridors that connect vulnerable habitats throughout the greater region. A striking example in the northwest portion of the expansion area is Bear Divide, which funnels thousands of migratory birds through a narrow pass along the Pacific Flyway, the primary avian migration route on the West Coast that extends from Central America to the Arctic. Another important corridor is the Arroyo Seco-Hahamongna Corridor, which connects the south-central portion of the expansion area to other nearby natural areas outside the Angeles National Forest boundary.
Despite its proximity to urban Los Angeles, the expansion area includes secluded and largely undeveloped areas such as the 4,700-acre Arroyo Seco Inventoried Roadless Area, which is an iconic landscape feature.
Protecting the expansion area will preserve an important spiritual, cultural, prehistoric, and historic landscape; maintain a diverse array of natural and scientific resources; and help ensure that the objects of historic and scientific interest within the area endure for the benefit of all Americans. As described above, the expansion area contains numerous objects of historic and scientific interest in need of protection. In addition, it provides exceptional outdoor recreational opportunities, including hiking, hunting, fishing, biking, horseback riding, backpacking, scenic driving, and wildlife viewing, all of which are important to residents of and visitors to the Los Angeles region.
WHEREAS, section 320301 of title 54, United States Code (the “Antiquities Act”), authorizes the President, in his discretion, to declare by public proclamation historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest that are situated upon the lands owned or controlled by the Federal Government to be national monuments, and to reserve as a part thereof parcels of land, the limits of which shall be confined to the smallest area compatible with the proper care and management of the objects to be protected; and
WHEREAS, I find that each of the objects identified above, and objects of the type identified above within the area described herein, are objects of historic or scientific interest in need of protection under section 320301 of title 54, United States Code, regardless of whether they are expressly identified as an object of historic or scientific interest in the text of this proclamation; and
WHEREAS, I find that there are threats to the objects identified in this proclamation, and in the absence of a reservation under the Antiquities Act, the objects identified in this proclamation are not adequately protected by applicable law or administrative designations, thus making a national monument designation and reservation necessary to protect the objects of historic and scientific interest identified above for current and future generations; and
WHEREAS, I find that the boundaries of the monument reserved by this proclamation represent the smallest area compatible with the proper care and management of the objects of scientific or historic interest identified above, as required by the Antiquities Act; and
WHEREAS, it is in the public interest to ensure the preservation, restoration, and protection of the objects of scientific and historic interest identified above;
NOW, THEREFORE, I, JOSEPH R. BIDEN JR., President of the United States of America, by the authority vested in me by section 320301 of title 54, United States Code, hereby proclaim the objects identified above that are situated upon lands and interests in lands owned or controlled by the Federal Government to be part of the San Gabriel Mountains National Monument and, for the purpose of protecting those objects, reserve as part thereof all lands and interests in lands that are owned or controlled by the Federal Government within the boundaries described on the accompanying map, which is attached hereto and forms a part of this proclamation. The reserved Federal lands and interests in lands within the expansion area encompass approximately 105,919 acres. As a result of the distribution of the objects throughout the area, the boundaries described on the accompanying map are confined to the smallest area compatible with the proper care and management of the objects of historic or scientific interest identified above.
Nothing in this proclamation shall change the management of the areas protected under Proclamation 9194. The terms, conditions, and management direction provided by Proclamation 9194, including any term limiting the construction or effect of Proclamation 9194, are incorporated by reference and shall apply to the area reserved by this proclamation except to the extent that they are inconsistent with a provision in this proclamation.
All Federal lands and interests in lands described on the accompanying map are hereby appropriated and withdrawn from all forms of entry, location, selection, sale, or other disposition under the public land laws or laws applicable to the Forest Service, other than by exchange that furthers the protective purposes of the monument; from location, entry, and patent under the mining laws; and from disposition under all laws relating to mineral and geothermal leasing.
This proclamation is subject to valid existing rights. If the Federal Government subsequently acquires any lands or interests in lands not currently owned or controlled by the Federal Government within the boundaries described on the accompanying map, such lands and interests in lands shall be reserved as a part of the monument, and objects of the type identified above that are situated upon those lands and interests in lands shall be part of the monument, upon acquisition of ownership or control by the Federal Government.
The Secretary of Agriculture (Secretary), through the Forest Service, shall manage the expansion area pursuant to applicable legal authorities and in accordance with the terms, conditions, and management direction provided by this proclamation and, as described above, those provided by Proclamation 9194.
The Secretary shall prepare, in consultation with the Secretary of the Interior, a management plan for the expansion area set forth in this proclamation, which shall include provisions for continuing outdoor recreational opportunities consistent with the proper care and management of the objects identified above, and shall promulgate such rules and regulations for the management of the expansion area as the Secretary shall deem appropriate. At the Secretary’s discretion, such management plan may be included as a component of the existing management plan developed pursuant to Proclamation 9194. The Secretary shall provide for maximum public involvement in the development of the management plan, including consultation with Tribal Nations and meaningful engagement with Indigenous peoples that have cultural, traditional, or ancestral ties to the area, with community environmental, conservation, health, and justice organizations, and with State and local governments. To the maximum extent practicable, the Secretary shall carefully incorporate Indigenous Knowledge in the development and implementation of the management plan, work with Tribal Nations to appropriately protect that knowledge, and, to the extent practicable, explain any limitations on the Secretary’s ability to protect such information from disclosure before it is shared with the Forest Service. The management plan shall provide for the protection and interpretation of the objects of scientific and historic interest identified above. The management plan shall also provide for continued public access to the area to the extent consistent with the protection of the objects identified above.
The Secretary, through the Forest Service, shall establish an advisory committee under chapter 10 of title 5, United States Code, to provide information and advice regarding the development of the management plan and management of the expansion area. The advisory committee shall consist of a fair and balanced representation of interested stakeholders, including State agencies and local governments; Tribal Nations and Indigenous peoples with cultural, traditional, or ancestral ties to the area; recreational users; conservation organizations; wildlife, hunting, and fishing organizations; the scientific community; business owners; and the general public in the region.
Nothing in this proclamation shall be deemed to revoke any existing withdrawal, reservation, or appropriation; however, the monument shall be the dominant reservation.
Warning is hereby given to all unauthorized persons not to appropriate, injure, destroy, or remove any feature of the monument and not to locate or settle upon any of the lands thereof.
If any provision of this proclamation, including its application to a particular parcel of land, is held to be invalid, the remainder of this proclamation and its application to other parcels of land shall not be affected thereby.
IN WITNESS WHEREOF, I have hereunto set my hand this second day of May, in the year of our Lord two thousand twenty-four, and of the Independence of the United States of America the two hundred and forty-eighth.
JOSEPH R. BIDEN JR.
