Area Description

The San Mateo Mountains are located in northern Sierra and southwestern Socorro Counties, 25 miles north of T or C, and 35 miles southwest of Socorro. Four units make up the complex described here. They are on opposite ends of the range with Peñasco Canyon and Peñasco Peak on the southeast end of the mountains, just south of Apache Kid Wilderness. Point of Rocks Canyon and Alexander Mountains are on the northwest portion of the mountains, just to the west of the Withington Wilderness. All four units are made up of a combination of Forest Service and BLM lands, encompassing a wide range of elevation and diversity of habitats.

In the northern units, grass-covered hills and mountains with pinyon-juniper woodlands and ponderosa pine characterize most of the area. Elevations range from 7,100 feet to over 8,400 feet on the BLM portions of the units. Point of Rocks Canyon itself is a wide, sandy wash where junipers and Apache plume grow. This vegetation transitions to oak-ponderosa woodlands in the canyon's upper reaches. Numerous drainages, including Kellog and Point of Rocks Canyons, cross the area and feed water into the closed basin of the Plains of San Agustin. In the south, Peñasco Canyon and Peñasco Peak are essentially one large unit because a single-wire power line on FS lands, with no route following it, is all that separates them. This area encompasses the foothills of the majestic Vicks Peak as it reaches southeast to the Chihuahuan Desert. Volcanic plugs jutting out of alluvium covered by desert shrubs characterize the unit. Elevations range from 4,940 to 6,131 feet on the BLM portions of the unit. The many long and fairly deep canyons within the units direct snow and rainfall to the nearby Rio Grande.

The San Mateo Mountains are a north-south trending fault block that has uplifted volcanic rocks from the Datil-Mogollon volcanic field over 3,000 feet on its east face. The Point of Rocks Canyon and Alexander Mountain units are on the edge of a volcanic caldron that encompasses essentially the entire Withington Wilderness at the north end of the range. This mountain range is also composed of volcanic and intrusive units, predominantly rhyolite ash-flow tuffs and lavas. Massive eruptions created these formations during a period of intense volcanic activity in the western US associated with the demise of the Farallon subduction zone and formation of the San Andreas Fault zone off the coast of California. The San Mateo tuffs and lavas were extruded around 28 and 24 million years ago. The most spectacular of the ash-flow tuff deposits is the Vick's Peak tuff, the 1,000-foot high cliffs forming the southernmost escarpment of the range. Uplift, faulting and weathering of these rocks during the past 20 million years has resulted in the incision of deep canyons along the flanks of the range.

Ecological Values

This area has high plant diversity because it lies within an ecoregion crossroads and has a large elevation gradient. All three major juniper types - mountain, alligator, and one-seed - can be found growing next to each other. There is a large diversity of grasses including vine mesquite, sideoats grama, blue grama, purple threeawn, silver beardgrass, wolftail, Indiangrass, sacaton, needle and thread grass, and burro grass. Other vegetation includes narrowleaf yucca, Torrey yucca, desert spoon sotol, prickly pear, cane cholla, pinyon pine, four-wing saltbush, Apache plume, broom dalea, desert holly, currant, scarlet globemallow, purple aster, sulfur buckwheat, and penstemon.

Protection of the BLM lands described here would round out protection of the San Mateo Mountains, which already have some of their high subalpine and montane conifer forests protected in the Apache Kid and Withington Wilderness areas. These areas represent the transition zone from the wooded, high elevation portion of the San Mateo Mountains to the grasslands of the Plains of San Agustin in the north, and the Chihuahuan Desert in the south. This makes it important to species that utilize both open and forested areas. Bear, mountain lion, bobcat, mule deer, pronghorn, coyote, turkey, kestrel, red tail hawk, golden eagle, and turkey vulture are found in the area. The NM Nature Conservancy has nominated the San Mateo Mountains as an Important Bird Area (IBA). As grassland songbirds continue their decline, the importance of protecting the grasslands found here greatly increases.

Scenic and Recreational Qualities

Compared to the higher elevation Apache Kid and Withington Wildernesses, the BLM units are more subtle in their beauty. From the rolling grass-covered hilltops in the north, there are commanding views across the Plains of San Agustin to Horse Peak and the Gallinas and Datil Mountains. In the south, the open terrain with lonely volcanic crags and plugs, and being adjacent to Vicks Peak, give Peñasco Canyon and Peñasco Peak exceptional scenic value. From the tops of these unit's volcanic plugs, views flow from the dramatic cliffs of Vicks Peak to the northwest to the vast expanse of the Chihuahuan Desert and Rio Grande Valley to the southeast.

Low visitor use in the lower elevation BLM areas ensures visitors will enjoy a primitive wilderness experience. Once one leaves the roads along the boundary of the units, they experience the peace and quiet of wilderness. Outstanding recreational opportunities here include wildlife viewing, cross-country hiking, hunting, geologic sightseeing, rock hounding, and nature photography.

Cultural Values

Prehistoric people have used the San Mateo Mountains for thousands of years. Little is known about the units described here, but archaeological sites likely exist. The grave of Apache Kid, a famous Apache chief, is located in the Apache Kid Wilderness. Just outside one of the units is a gold mining ghost town, Rosedale, that had a maximum population of approximately 100 people. Mining operations there ceased around 1940.

Access Information

Easy access to the southern end of the range is available from FR 139 and FR 225, which form a loop off of Hwy 1, which you can get to from exits 92, 100, and 115 off of I-25. This takes you around the Peñasco Canyon/Peñasco Peak unit.