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Trinity Alps near Granite Lake
|Elevation||2,744 m (9,003 ft)|
The Trinity Alps are mountains in Northern California, in the Pacific Coast Ranges physiographic region, located to the northwest of Redding. Elevations there range from 1,350 feet (411 m) to 9,001 ft (2,744 m) at Thompson Peak. The Trinity Alps Wilderness covers 517,000 acres (2,090 km2), making it the second largest wilderness area in California. The area was formerly known as the Salmon-Trinity Alps Primitive Area since 1932 until a series of expansions. The Trinity Alps are situated within the Klamath Mountains Range, which lies between the Pacific Coast Ranges to the west and the Cascade Range further to the east. The Trinity Alps are noted for their scenic views and alpine environment, which differ from those found in the Sierra Nevada, the Coastal Range, or the Cascades. The northern backbone of these mountains is the Salmon and Scott Mountains.
According to recent, but incorrect, USGS maps, 35 permanent bodies of snow and several tiny glaciers dot the highest peaks of the Alps. Independent study has shown that only about six of these snow/ice bodies persist through the driest years. The recent 7.5-minute topographic maps from the USGS severely overstate the area of these ice bodies; for example, none of those shown on the east side of the ridge west of Canyon Creek or of Sawtooth Peak remain at the end even of half the years. The only one that is unambiguously a glacier is the 15-acre (61,000 m2) icefield on the north side of Thompson Peak, which shows crevasses indicating true motion even on so small an icefield. Research has shown that some glaciers in the Trinity Alps are more resistant to the effects of global warming than are other California glaciers.
Temporary glacier 
On the ridge south of Sapphire Lake is an unusual phenomenon consisting of a temporary glacier, versus an inactive snowfield that melts out in dry years. Following years of heavy accumulation, an icefield appears in this fully sheltered north-facing cirque that can show active crevasses and seracs some tens of feet high. But this ice body, at an elevation of only 7,500 ft (2,300 m) in a region experiencing a long, hot dry season from about mid May to mid October, can disappear completely during a run of drier years. The lowest snowfield in California that does not disappear except in the extreme runs of dry years is located above Mirror Lake at an elevation of 6,600 ft (2,000 m). Studies of lichen collars indicate that the site near Kalmia Lake is the snowiest spot in the State of California, receiving snow accumulation in excess of the Lake Helen snowcourse on Lassen Peak, by far the snowcourse with greatest late winter snow accumulation in California. This in turn is consistent with the fact of an active glacier under Thompson Peak, while, in contrast, no such active glacier exists under Brokeoff Mountain west of Lassen Peak, higher than Thompson Peak and presenting an ideal NNE-facing zone in the area of maximum snow accumulation beneath an almost-vertical cliff face 1,000 ft (300 m) high. Sufficient snow does accumulate under Brokeoff that in some years the snowfield there experiences incipient glacial motion. Two moraines below it, one very recent, provide clear evidence at least of mass transport in the recent past at that site. These moraines are quite a bit smaller than those found below the Thompson Peak glacieret.
This region of the Klamath Mountains is also outstanding for having the greatest number of conifers of any place in the world except one. Russian Peak in the Russian Wilderness just north of the Trinity Alps has the greatest number of conifer species in North America. The northern species, such as subalpine fir (Abies lasiocarpa), Pacific silver fir (Abies amabilis), and Engelmann spruce (Picea engelmannii) are found here, as well as the trees from the south, such as incense cedar (Calocedrus decurrens), ponderosa pine (Pinus ponderosa), and white fir (Abies concolor), plus unique populations of foxtail pine (Pinus balfouriana) and weeping spruce (Picea breweriana). So many types of conifers can exist together because the range is at the intersection of the Mediterranean climate of the south and the northwestern coastal climate, which has a shorter dry season. Other plants along the trails include the carnivorous California pitcher plant (Darlingtonia californica), the showy pinkish Lewisia cotyledon, and the rare Trinity Alps endemic wildflower Trinity penstemon (Penstemon tracyi). Sagebrush is found on ridges in the Scott Mountains.
Most of the lakes have been stocked with rainbow, brown or brook trout, and some have self-sustaining populations. The major streams of the North Fork Trinity River and New River watersheds have spawning chinook salmon, and some have steelhead including rare summer steelhead. The Trinity Alps are home to much wildlife including: American black bear, blacktailed deer, lizards, chipmunks, and a great number of bird species. Deer and black bear are commonly seen. Less common but present are mountain lion, pine marten, fisher, and wolverine. California newts are commonly found in ponds and lakes. The Trinity Alps may be home to a cryptozoological phenomenon, the Trinity Alps Giant Salamander.
The US Forest Service, Shasta-Trinity National Forest, manages most of the Trinity Alps Wilderness. The northern boundary extends into the Klamath National Forest, and the western boundary extends into the Six Rivers National Forest. There are also private inholdings, especially in the eastern portions. The wilderness contains hiking trails, backcountry camping, and beautiful scenery. Access is off state Highways 299 on the south, 3 on the east, and various old logging and mining roads on the north and west. Most of the area is visited much less heavily than many other wilderness areas in California, such as in Yosemite National Park or Kings Canyon National Park but more heavily than the nearby Yolla Bolly-Middle Eel Wilderness.
The most popular destinations beyond the trailheads are Canyon Creek Lakes, Emerald and Sapphire Lakes on the Stuart Fork, and Granite Lake up the Swift Creek trail. The western ridges are mostly lower in elevation with fewer lakes, and ridgetop trails there can be hot and dry in the summer. Less-visited areas include New River, Salmon Mountain, Horse Linto Creek, Pony Buttes, and Limestone Ridge in the west, and Packers Peak, Deadman Peak, and Eagle Peak in the Scott Mountains. The Trinity Alps overlook Trinity Lake to the east, a large reservoir of the federal Central Valley Project on the Trinity River. Many higher lakes, such as Grizzly, Smith, and Mirror rival the most spectacular high lakes in the Sierra Nevada. Trails do not reach all of the lakes but cross-country routes are possible. Wilderness permits are required. The Pacific Crest Trail connects the northeast corner of the Trinity Alps to the Russian Wilderness and Marble Mountain Wilderness to the north and the Castle Crags Wilderness in the Trinity Divide to the east. Large fires have burned through some of the forests in the wilderness, including much of the 105,855-acre (428.38 km2) Iron/Alps Complex fire in 2008. Rockclimbing is excellent in the areas such as Caribou Peak and Sawtooth Ridge with granite cliffs. Hunting is good for deer, bear, and bandtailed pigeon in season.
Geologically, the Trinity Alps consist of a mixture of igneous, granite and metamorphic peaks. In the eastern mountains are the Red Trinities, due to reddish ultramafic peridotite, in the central granitic batholith are the White Trinities, and in the western mountains are the Green Trinities due to more extensive forest cover. The region contains much pine and fir forest as well as meadows, creeks, and lakes.
- "Trinity Alps". Geographic Names Information System, U.S. Geological Survey. Retrieved 2009-05-03.
- "Trinity Alps Wilderness". Orbitz Away LLC. Retrieved July 17, 2007.
- University Of California - Santa Barbara (May 7, 2005). "Small Glaciers In Northern California Buck Global Warming Trend.". ScienceDaily. Retrieved May 16, 2012.
- Munz, P. A. & D. Lake. Introduction to California Mountain Wildflowers.