Interstate 15

Eastern Mojave Vegetation	U. S. Interstate 15
	Tom Schweich

Topics in this Article: Montana Idaho Utah Leeds Arizona Nevada California Literature Cited	(No Preface)
	U. S. / Canada Border
	Montana
	Sweetgrass
	Butte
	Junction: U. S. Interstate 90
	Montana above … Idaho below …
	Idaho
	Pocatello
Other Articles: U. S. Highway 91: at US I-15	Jct: US Hwy 91, south past Zenda to Logan, then west back to US I-15.
	Idaho above Utah below
	Utah
	Tremonton Jct: I-84
Other Articles: U. S. Highway 91: Brigham City	Brigham City Junction: US Hwy 91, east to Logan, then north back to US I-15. A reason to take US Highway 91 as an alternate to Interstate 15 would be to see the spillway of Pleistocene Lake Bonneville into the Snake River drainage. The bedrock threshold that established the Provo shoreline is at Red Rock Pass, while an earlier failed alluvial dam is placed at Zenda.
Locations: Salt Lake City.	Salt Lake City
Other Articles: Interstate 80: at US I-15 North	Junction: U. S. Interstate 80, West.
Other Articles: Interstate 80: at US I-15 South	Junction: U. S. Interstate 80, East.
Locations: Scipio.	Scipio
Other Articles: U. S. Highway 50: at US Hwy 50 North	Junction: U. S. Highway 50, East.
Locations: Holden.	Holden
Other Articles: U. S. Highway 50: at US Hwy 50 South	Junction: U. S. Highway 50, West.
Other Articles: Interstate 70: at US I-15	Junction: U. S. Interstate 70.
Other Articles: Utah Highway 21: Beaver	Beaver Junction: UT Highway 21, west through Minersville and Milford to the Nevada border near Great Basin National Park and US Highway 50.
	Beaver River basin to the north ... Beaver Ridge Parowan Valley to the south.
	Beaver County above … Iron County below …
Locations: Parowan Valley.	Parowan Valley
	Junction: Utah Highway 271, access road to Paragonah.
Locations: Paragonah. Red Creek.	Paragonah Red Creek exits through the Hurricane Cliffs into Paragonah. On Red Creek, S. L. Welsh made a collection of Swertia albomarginata.
	Parowan
Locations: Cedar City.	Cedar City
Other Articles: Utah Highway 56: at US I-15	Junction: Utah Highway 56, West to Nevada.
Other Articles: Utah Highway 14: Cedar City	Junction: Utah Highway 14, East.
Fort Harmony and the Harmony Mountains across US I-15. Other Articles: Field Notes: May 31st, Kolob Cyns.	View of Fort Harmony, and the Harmony Mountains across US Interstate 15.
Cheryl and Tom at the Kolob Canyons Overlook. Other Articles: Field Notes: May 31st, Kolob Cyns. Locations: Kolob Canyons, Zion National Park.	Overlook in Kolob Canyons, Zion National Park.
Looking southwest along US I-15 near Kolob Canyons. Other Articles: Field Notes: May 31st, Kolob Cyns.	View southwest toward Saint George along US Interstate 15.
Other Articles: Blackbrush: 406500 Utah Highway 17: Anderson Junction	Anderson Junction Junction: Utah Highway 17, South to Toquerville.
Literature Cited: - Post, Douglas M., 1956. Other Articles: Swertia albomarginata: in Pine Vy Mtns Locations: Italian Spring.	Cross Grapevine Wash. Grapevine Wash drains Italian Wash, which drains Italian Spring. There is a collection of Swertia albomarginata from Italian Spring.
Other Articles: Oak Grove Road: at US I-15	Exit 23: Silver Reef Road, to Oak Grove Road and the Oak Grove Campground.
Other Articles: Swertia albomarginata: in Pine Vy Mtns Locations: Silver Reef.	Leeds Site of Silver Reef to the north.
Other Articles: Utah Highway 9: at US I-15	Junction: Utah Highway 9, east to Hurricane and Zion National Park.
	Exit 8: Saint George Blvd., UT Highway 34
Other Articles: U. S. Highway 91: at St. George Locations: Saint George.	Saint George
Other Articles: Utah Highway 18: at US I-15 Riverside Drive: 10000	Exit 6: Bluff Street, UT Hwy18, west side of St. George. Riverside Drive, to southeastern Saint George.
Virgin River Gorge Recreation Area, Washington County, Utah Other Articles: Field Notes: 20050530070 Locations: Virgin River.	Virgin River Gorge Recreation Area. We stopped here for lunch one time and watched some rafters launch their raft, and drift downstream into the gorge.
Virgin River in its gorge, near the upper end. Other Articles: Field Notes: in Virgin River Gorge. Locations: Virgin River.	I have driven through the Virgin River Gorge on US I-15 twice in the northeasterly direction, and neither time have I seen a good place to stop for a photograph.
	Utah above. Arizona below.
	Arizona
Other Articles: Black Rock Mountain Road: at US I-15	Exit 27: Black Rock Mountain Road
Locations: Beaver Dam Mountains. Virgin Mountains.	Beaver Dam Mountains to the northwest. Vrigin Mountains to the southeast.
Other Articles: U. S. Highway 91: Littlefield Locations: Littlefield.	Littlefield
Literature Cited: - Comstock, J. P., T. A. Cooper, and J. R. Ehleringer, 1988. Other Articles: Summaries of Literature: Patterns of Canopy Development and Carbon Gain	The road north from Littlefield goes to the Joshua Tree Natural Area in southwestern Utah. I have been unable to find a name for this road. Comstock, Cooper and Ehleringer's (1988) site two for their study of patterns of canopy development and carbon gain is 16 km north of Littlefield within the Joshua Tree Natural Area.
	Arizona above … Nevada below …
	Nevada
	Mesquite
	Bunkerville to the southeast across the Virgin River.
Literature Cited: - Kartesz, John Thomas, 1988. Locations: Virgin Mountains.	Virgin Mountains in Clark County, Nevada, to the southeast across the Virgin River.
Other Articles: NV State Route 12: at US I-15	Junction: Nevada State Route 12
Other Articles: NV State Route 169: at US I-15	Junction: Nevada State Route 169
Other Articles: U. S. Highway 93: at US I-15	Junction: U. S. Highway 93, North.
	Las Vegas, North City Limit.
Other Articles: U. S. Highway 95: Las Vegas U. S. Interstate 515: 11000 U. S. Highway 93: at US I-15	Junction: U. S. Interstate 515, southeast through Las Vegas to Henderson, Nevada. U. S. Highway 93, south to Kingman, Wickenburg and Phoenix. U. S. Highway 95, north, to Beatty, Tonopah, Fallon, etc., south to Searchlight.
Other Articles: Nevada State Route 159: at US I-15	Junction: Nevada State Route 159 "W. Charleston Blvd."
Locations: Las Vegas.	Las Vegas
	Las Vegas, South City Limit.
Other Articles: NV Highway 160: 60000	Junction: Nevada Highway 160, the Blue Diamond Highway, which goes to Blue Diamond, and Pahrump.
Locations: Potosi Mountain.	The high mountain to the west of U. S. Interstate 15 is Potosi Mountain, considered to be a southern extension of the Spring Mountains.
Other Articles: NV Hwy 161: Jean Locations: Goodsprings. Jean. Sheep Mountain.	Jean Junction: NV Hwy 161, to Goodsprings and Sandy Valley Sheep Mountain, type locality of the Goodsprings Dolomite, is across the valley to the southeast.
Literature Cited: - Guest, Bernard, Nathan Niemi, and Brian Wernicke, 2007. Devil Peak at the south end of the Mesquite Valley Other Articles: Glossary: hypabyssal Locations: Devil Peak.	Devil Peak to the northwest. Devil Peak is a small (~2.5 km diameter) hypabyssal rhyolite dome that intruded into Paleozoic carbonate strata of the southern Spring Mountains (Guest, et al., 2007). It is also the probable source for megabreccia sheets, pyroclastic deposits, and obsidian rock avalanche deposits that make up the crest of Black Butte. These deposits are evidence for about 30 km of dextral slip along the Stateline Fault System.
Primm, Nevada, as seen from the northeast slopes of Clark Mountain. Locations: Primm.	Primm
Other Articles: Keany Pass Road: at Primm	Junction: Keany Pass Road.
	Nevada above … California below …
	California
Ivanpah Lake and Primm Other Articles: Nipton Road: 10000 Locations: Lakeview.	Junction: Nipton Road. This is the former location of Lakeview, California. Annie Alexander and Louise Kellogg collected here on May 17, 1940. I found the location indicated on a 1939 edition of a AAA highway map.
View of the Unocal processing plant at the Mountain Pass Rare Earth Mine Other Articles: Zinc Mine Road: at Mountain Pass Locations: Mountain Pass.	Mountain Pass The largest known rare earth deposits in the world exist near Mountain Pass Summit. Today, the Molybdenum Corporation of America is processing the highly concentrated rare earth ore, the only remaining productive mining activity in the area. Prior to 1924, an unpaved road known as Arrowhead Trail, which was oil-treated shortly thereafter, generally followed meandering "dry" streambeds through Mountain Pass and Wheaton Canyon. Between 1933 and 1937, a greatly improved two-lane highway was constructed, which served as U.S. Highway 91 and 466 until 1963.
Location of Clark Mountain Station. Locations: Clark Mountain Station.	Clark Mountain Station Annie Alexander and Louise Kellogg stayed at Clark Mountain Station May 12-16, 1939.
Other Articles: Kessler Springs Road: at Valley Wells Kingston Road: Valley Wells Locations: Valley Wells.	Valley Wells No gasoline (May 2000, September 2000). Gasoline (May 2003) Junction: Kingston Road, north, leads to Excelsior Mine Road and the Kingston Range. This is a good road that ultimately leads to Tecopa Hot Springs on California Highway 127. Kessler Springs Road, south, is one gateway road into the Mojave National Preserve.
Clark Mountain, California, from Halloran Summit. Locations: Clark Mountain. Halloran Summit. Yucca Grove.	Halloran Summit Gasoline and some services available (September 2000). I believe this is the former location of Yucca Grove. It was on the north side of then US Highways 91 and 466, and included an Auto Camp, in addition to gasoline and other services.
Other Articles: Halloran Springs Road: at Halloran Springs at US I-15 Locations: Halloran Springs.	Halloran Springs No services (September 2000) Junction: Halloran Springs Road, west to Silver Lake on California Highway 127.
The World's Tallest Thermometer in Baker, CA. The Mad Greek Restaurant in Baker, California. Other Articles: Tonopah & Tidewater: Baker California Highway 127: at Baker Kelbaker Road: in Baker Locations: Baker.	Baker Road Junctions at Baker: Kelbaker Road, south is one gateway road into Mojave National Preserve, leading through the Cima Volcanoc Field to Kelso, and then to U. S. Interstate 40. California Highway 127, the southern gateway to Death Valley, north to Shoshone and Death Valley Junction.


	View of Little Cow Hole Mountain. The photo is taken from Zzyzx Road, but a similar view can be had from US I-15.
The Zzyzx Road exit from Interstate 15 Other Articles: FAQ: Zzyzx Zzyzx Road: at US I-15 Locations: Zzyzx.	Junction: Zzyzx Road
	Soda Springs Desert Studies Center
Literature Cited: - Schoenherr, Allan A, 1992. Class at Desert Studies Center.	I've been privileged to stay here for several classes and field trips. In this photograph, Allan Schoenherr, author of A Natural History of California, leads an early morning field trip to examine traps set along a transect the previous night. For information about the center see, http://biology.fullerton.edu:80/facilities/zzyzx.html
Soda Mountains from the shores of Soda Lake. Locations: Soda Mountains.	Soda Mountains to the north.
Literature Cited: - Laity, June, 2000. Ventifact on top of Ventifact Hill U. S. Interstate 15 looking east toward Baker and Las Vegas from Ventifact Hill	Ventifact Hill The easily accessible vertifacts at "Ventifact Hill," east of Afton Canyon, are just a few of the many spectacular examples of sandblasted rocks that are to be found in the east-central Mojave Desert. They have formed in a corridor of wind transport which moved sand from the Mojave River eastward through the Devil's Playground, and ultimately towards the Kelso Dunes. Most of the ventifacts in this region are fossil or relict in nature, attesting to a time of greater sediment availability and possibly higher velocity winds. Today, areas of active ventifact formation are limited to a few hill crests where dune sand is being reworked by bidirectional winds (From the Author's Introduction, Laity, 2000).
Literature Cited: - Evans, James R., 1962. The Cronese "Cat" Other Articles: Eastern Mojave Geology: 595110	The Cronese "Cat," a falling sand dune on the west side of the Cronese Basin, as seen from US Interstate 15. Evans (1962) studied these sand dunes, and his work is summarized in my article on eastern Mojave geology.
Other Articles: Field Notes: 200004260090 Basin Road: 50000 Locations: Cronese Basin.	Junction: Basin Road.
Cronese Basin with Cave Mountain.	The Cronese Basin with Cave Mountain on the south (left) side. The Basin Road overpass over U. S. Interstate 15 can be seen at the extreme left.
Literature Cited: - Meek, Norman, 2000. Field trip stop on the shore of Lake Manix Other Articles: Field Notes: 20050419080 Afton Road: 12000 Locations: Afton Canyon.	Junction: Afton Road The history of lakes in the eastern Afton basin is very short compared with most Mojave Desert basins. The basin apparently did not exist prior to the rapid rise of the Cady Mountains in the Middle Pleistocene, as the oldest lacustrine evidence in eastern Afton basin is no older than about 300 ka. Afton area lacustrine sections provide evidence for three major lake events. The most prominent lake stand occurred during OIS 6 (Illinoian). All of the thick green clays visible in the Afton area are from this lake stand. Some of the clays have gypsum crystals, suggesting that this lake eventually dessicated. The Illinoian lake was followed by a lengthy dry interval probably starting in the Sangamon (OIS 5e). Next a tufa deposit dated at 80 ka, suggests that an OIS 4 lake reached an elevation of 525 m. Correlable strata are located near Camp Cady. Finally, there are several beach ridges and tufas at elevation of 542.5 m, show in the photograph at left, that have been reliably dated by radiocarbon methods to between 21.5 and 18 ka. This is slightly above the approximate elevation of the topographic divide into Coyote Basin, suggesting the maximum level of Lake Manix was maintained internally by overflows into Coyote Basin. Sometime about 18 ka., water overtopped the lowest rim of the Manix basin immediately above Afton Canyon and the water spilled out, removing that part of the canyon above the lake floor in a matter of hours. Since that time the Mojave River has continued to cut Afton Canyon, and the landscape is still adjusting to the rapid base level drop (Meek, 2000)
Who is this guy? Why does he keep showing up in my Mojave Desert photos?	Between Field Road and Afton Road, US I-15 passes through lake beds of Pleistocene Lake Manix.
	Junction: Field Road, access to Field, a station on the Union Pacific, and access to Camp Cady Wildlife Area via Yermo Road.
	Manix Overcrossing, Alvord Mountain Road. There is no freeway exit here. The nearest exits are Harvard Road to the west and Field Road to the east.
	Camp Cady Wildlife Area
Vicinity of Camp Cady on the Mojave River. Locations: Camp Cady.	Camp Cady Former military fort, guarding the Mojave Road, on the Mojave River about 1 1/2 miles south of US I-15.
Literature Cited: - Laity, June, 2000. Agriculture in the Central Mojave. Other Articles: Field Notes: 20020420070 Locations: Harvard Hill.	There are many ranches in the Lower Mojave Valley that rely on pumping of groundwater for the crops. The combination of soil disturbance and declining water tables has destabilized the landscape resulting in increased sand movement and dust storms that have been blamed for fatal highway accidents (Laity, 2000).
	Junction: Harvard Road, access to Harvard Hill, east to Camp Cady Wildlife Area, and south across Mojave Valley to Newberry Springs.
Climax vegetation on Harvard Hill. US I-15 as seen from Harvard Hill. Other Articles: Field Notes: 20020420070 Locations: Harvard Hill.	Harvard Hill
	Minneola Road
View of Mojave Valley from Dagget Ridge
	Junction Road: Calico Road.
Other Articles: Old California Highway 58: 16000	Junction: Old California Highway 58
Locations: Barstow.	Barstow California city, crossroads for early emigrant trails, railroads and highways in the California Desert, on the Mojave River. Once a small mining center and railroad town in California's Mojave Desert, Barstow is located at the junction of 3 major highways -- Interstate 15, Interstate 40 and State Highway 58. It is centrally located in the western Mojave at the entrance to the Mojave National Preserve and is home of the U.S. Army National Training Center, Marine Corps Logistics Base, NASA's Goldstone Deep Space Network and Burlington Northern-Santa Fe Railroad Yards. Population is 21,500 and elevation is 2,106 feet above sea level
Other Articles: U. S. Interstate 40: at Barstow	Junction: U. S. Interstate 40.
Other Articles: California Highway 247: at US I-15	Junction: Barstow Road, California Highway 247
Other Articles: California Highway 58: just west of Barstow	Junction: California Highway 58, west through Mojave and Bakersfield to US Highway 101 at Santa Margarita.
Other Articles: Lenwood Road: 80000	Junction: Lenwood Road.
Locations: Victorville.	Victorville
Other Articles: California Highway 18: at US I-15 N	Junction: California Highway 18, east to Apple Valley, and Lucerne Valley.
Other Articles: California Highway 18: at US I-15 S	Junction: California Highway 18, west to Palmdale and US I-5 near Gorman
Locations: Hesperia.	Junction: Phelan Road, Hesperia to the east.
Other Articles: U. S. Highway 395: at US I-15	Junction: U. S. Highway 395.
	Cajon Pass
Other Articles: California Highway 138: Cajon Junction	Junction: California Highway 138
Other Articles: US I-10: 10992	Junction: U. S. Interstate 10, west to Los Angeles, east to San Bernardino.
Other Articles: California Highway 78: at US I-15	Junction: California Highway 78
Locations: San Diego.	San Diego
	Literature Cited A list of all literature cited by this web site can be found in the Bibliography.
	Comstock, J. P., T. A. Cooper, and J. R. Ehleringer. 1988. Seasonal patterns of canopy development and carbon gain in nineteen warm desert shrub species. Oecologia (Berlin). 75(3):327-335. {TAS} ...
	Evans, James R. 1962. Falling and climbing sand dunes in the Cronese ("Cat") Mountain area, San Bernardino County, California. Journal of Geology. 70: 107-113. {TAS} Location records referred to by this literature: Cronese Basin, San Bernardino County, California.
	Guest, Bernard, Nathan Niemi, and Brian Wernicke. 2007. Stateline fault system: A new component of the Miocene-Quaternary Eastern California shear zone. GSA Bulletin. 119(11/12):1337-1346. {TAS&pdf} Location records referred to by this literature: Black Butte, Clark County, Nevada. Devil Peak, Clark County, Nevada.
	Kartesz, John Thomas. 1988. A flora of Nevada. Ph.D. dissertation, University of Nevada, Reno, 1988.. Location records referred to by this literature: Spring Mountains, Clark County, Nevada. Virgin Mountains, Clark County, Nevada. Pinto Canyon, Eureka County, Nevada. Secret Canyon, Eureka County, Nevada. Cave Valley, Lincoln County, Nevada. Groom Range, Lincoln County, Nevada. Long Valley, White Pine County, Nevada. White Pine Range, White Pine County, Nevada.
	Laity, June. 2000. Ventifacts in the Mojave River Corridor and at "Ventifact Hill". pp. 37-39 in Reynolds, Robert E., and Jennifer Reynolds, 2000. Empty Basins, Vanished Lakes: A Field Guide to Afton, Baxter, Tecopa, Shoshone, Pahrump and Kingston. San Bernardino County Museum Association Quarterly. 47(2). Redlands, CA: San Bernardino County Museum Association, 2000. ...
	Laity, June. 2000. The Lower Mojave Valley: Mojave Desert, California: A Destabilizing Aeolian Environment (Abstract). pp. 78-79 in Reynolds, Robert E., and Jennifer Reynolds, 2000. Empty Basins, Vanished Lakes: A Field Guide to Afton, Baxter, Tecopa, Shoshone, Pahrump and Kingston. San Bernardino County Museum Association Quarterly. 47(2). Redlands, CA: San Bernardino County Museum Association, 2000. ... Location records referred to by this literature: Harvard Hill, San Bernardino County, California.
	Meek, Norman. 2000. The Late Wisconsinian History of the Afton Canyon Area. pp. 32-34 in Reynolds, Robert E., and Jennifer Reynolds, 2000. Empty Basins, Vanished Lakes: A Field Guide to Afton, Baxter, Tecopa, Shoshone, Pahrump and Kingston. San Bernardino County Museum Association Quarterly. 47(2). Redlands, CA: San Bernardino County Museum Association, 2000. ... Location records referred to by this literature: Afton Canyon, San Bernardino County, California.
	Post, Douglas M. 1956. Studies in the Gentianaceae: Frasera and Swertia of North America. Ph.D. dissertation. University of California, Berkeley. 1956.. Location records referred to by this literature: Petrified Forest National Park, Apache County, Arizona. Johnson, Cochise County, Arizona. Grand Canyon, Coconino County, Arizona. Oak Creek Canyon, Coconino County, Arizona. Bucksin Mountain, La Paz County, Arizona. Hualapai Mountains, Mohave County, Arizona. Mokiak Pass, Mohave County, Arizona. Pipe Spring, Mohave County, Arizona. Vermillion Cliffs, Mohave County, Arizona. Keystone Canyon, San Bernardino County, California. Providence Mountains, San Bernardino County, California. Mesa Verde, Montezuma County, Colorado. Mesa Verde National Park, Montezuma County, Colorado. Pleasant View, Montezuma County, Colorado. Soda Canyon Tip-off Trail, Montezuma County, Colorado. Deadman Canyon, Clark County, Nevada. Yank Pit Canyon, Clark County, Nevada. Currant Creek, Elko County, Nevada. Adams Hill, Eureka County, Nevada. Pinto Summit, Eureka County, Nevada. Mount Irish, Lincoln County, Nevada. Mount Irish Range, Lincoln County, Nevada. Pahranagat Range, Lincoln County, Nevada. Miller Canyon, Carbon County, Utah. Bluff, San Juan County, Utah. White Mesa, San Juan County, Utah. Italian Spring, Washington County, Utah. Oak Grove Campground, Washington County, Utah. Pine Mountain, Washington County, Utah. Capitol Reef National Park, Wayne County, Utah.
	Schoenherr, Allan A. 1992. A Natural History of California. Berkeley, CA: University of California Press. {TAS} 772 p. Location records referred to by this literature: Great Basin Desert, Esmeralda County, Nevada.
If you have a question or a comment you may write to me at: tas4@schweich.com I sometimes post interesting questions in my FAQ, but I never disclose your full name or address.	[Home Page] Date and time this article was prepared: 5/8/2008 9:43:27 AM

Montana

Sweetgrass

Butte

Idaho

Pocatello

Utah

Tremonton

Brigham City

Salt Lake City

Scipio

Holden

Beaver

Parowan Valley

Paragonah

Parowan

Cedar City

Anderson Junction

Leeds

Saint George

Arizona

Littlefield

Nevada

Mesquite

Las Vegas

Jean

Primm

California

Mountain Pass

Clark Mountain Station

Valley Wells

Halloran Summit

Halloran Springs

Baker

Ventifact Hill

Barstow

Victorville

Cajon Pass

San Diego

Literature Cited