
Cottonwood Canyon (view northwest) |
Overview
Jumbo Springs is small (4,631 acres) wilderness area, measuring only 3.5 miles long and 1.5 miles wide. What it lacks in size, it makes up for in that it is located in a remote, sparsely-vegetated, rugged region of granitic ridges and canyons on the far east end of Lake Mead. The area sits on the southeast side of Jumbo Peak, uphill from the boundary of Lake Mead National Recreation Area. Three major washes cut across the wilderness area, draining east and south towards the lake. Elevations range from 4,700 feet on a ridge in the northwest side, to washes at about 2,700 feet along the southeast side of the area. The area offers grand views of Lake Mead and the lower reaches of the Grand Canyon. Water can be found in springs and in the granite, water-polished potholes in Cottonwood Spring. |

South end, view east from Scanlon Ferry Road |
If you hike in wilderness areas, help protect them by learning about and reporting noxious and invasive weeds.
Link to map of the wilderness area.
Link to hikes in the wilderness area.
Location
The Jumbo Springs Wilderness Area is located about 55 air-miles east of Las Vegas, out in the Gold Butte Region north of Lake Mead and east of the Overton Arm. |

South end, view north from Scanlon Ferry Road |
Boundaries
The boundaries of this small wilderness area are not easily defined by geologic features, political boundaries, of section lines. Rather, the boundary was drawn to include rocky cliffs and mountain hillsides south and east of Jumbo Peak and Jumbo Spring.
The wilderness area aligned north-south. The area is about 2-miles wide at the southern and northern ends and about 1-mile wide in the middle. The northern boundary runs east-west from near Jumbo Peak to Cottonwood Canyon. The eastern boundary follows section lines 1 mile west of the Lake Mead NRA boundary. The southern boundary follows section lines along the Lake Mead NRA boundary. The western boundary follows the top edge of the cliffs. |

Cottonwood Canyon (view northwest) |
Access
Access is from the Devils Cove Road (rough dirt) that runs near the eastern boundary of the wilderness area. A short spur road leads to a parking area at the base of Cottonwood Canyon. From the west side, access if from Scanlon Ferry Road (very rough dirt.) |

Granite outcrops (view northwest). |
Terrain
The wilderness area is located on the southeast flanks of Jumbo Peak and includes the upper canyons of three major washes that drain toward Lake Mead. Elevations range from 2,700 feet along the southern boundary to the 4,700-foot ridge on the northern end. The area includes sparsely vegetated granitic ridges and canyons that overlook the eastern end of Lake Mead. There are granitic domes and smooth cliffs along the ridge tops, and the side slopes are strewn with coarse-grained granitic boulders and deeply cut by canyons. |

Creosote bush and boulders (view northwest) |
Habitat Type
The side slopes are rocky and sparsely vegetated with a fair variety of Mojave Desert Scrub species that include creosote bush, catclaw acacia, Mojave yucca, Nevada jointfir, buckwheat, a few cacti (e.g., Beavertail and mound cactus), and in some places, even cryptobiotic crusts. There are lots of barrel cactus on the more rocky slopes. In Cottonwood Canyon, the dominant shrubs include rabbitbrush, catclaw acacia, desert willow, honey mesquite, and buckhorn cholla. Above one waterfall, there is enough water to support cattail and bulrush, and unfortunately, there is a fair bit of saltcedar too. |

Lake Mead as seen from the northern boundary of the wilderness area (view south). |
Wildlife
Mammals include desert bighorn sheep, coyote, and black-tailed jackrabbits, burros or horses (droppings), desert woodrats, white-tailed antelope squirrels, and pocket gophers. Reptiles include desert tortoise and side-blotched lizards. Birds include Red-Tailed Hawk, Cooper's Hawk, Golden Eagle, Gambel's Quail, Greater Roadrunner, White-crowned Sparrow, and Black-throated Sparrows.
Archaeology
No information, but there is water here, so there probably were people here too. |

Rocky crags with Mojave Yucca (view west). |
Geology
The geology of the general area is complex, with a variety of oddly juxtaposed rock types. In the wilderness area, all of the rocks are old and date to Precambrian times. The lower strata is Precambrian metamorphic, but this is overlain by what seem be regular, coarse-grained granitic rocks. There are granitic domes and smooth cliffs along the ridge tops, and the side slopes are strewn with coarse-grained granitic boulders and deeply cut by canyons. Just across the road to the east, the rocks are carbonates with dates starting in the Cambrian. On some of the water-polished granite waterfalls, there are carbonate flowstone-like deposits, but I don't know what the source of the carbonates would be on this side of the canyon; maybe it isn't carbonate. The granitic boulders and cliffs in the wilderness area remind me of Joshua Tree National Park. |
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