Pinkham Notch (elevation 2032 ft. / 619 m) is a mountain pass in the White Mountains of north-central New Hampshire, United States. The notch is a result of extensive erosion by the Laurentide Ice Sheet during the Wisconsinian ice age. Pinkham Notch was eroded into a glacial U-shaped valley whose walls are formed by the Presidential, Wildcat, and Carter-Moriah ranges. Due to the volatility of the area's climate and rugged character of the terrain, a number of rare or endemic ecosystems have developed throughout the notch.

The presence of the notch was recorded in 1784 by Jeremy Belknap, but its isolation prevented further development for several years. The construction of New Hampshire Route 16 has led to increased accessibility and a rise in tourism. Its location makes it a hub for hiking and skiing.

Geography The notch separates the Presidential Range, which forms the western wall, from the Wildcat Range, which forms the eastern wall. Two rivers drain the notch; the Ellis River drains the south end and is a tributary of the Saco, and the Peabody River drains the north end and is a tributary of the Androscoggin.USGS 7.5 Minute Topographic Map Series: Mount Washington, Stairs Mountain, Carter Dome, Jackson Quadrangles.

The bulk of the western slope of the notch is formed by Mount Washington, the highest peak in the northeast United States, reaching above sea level.Daniell, Gene, and Smith, Steven D. White Mountain Guide. 27th ed. AMC Books, 2003. . p. 9. Mount Washington rises more than above the floor of the notch. A number of glacial cirques are found on this side of the notch. The Great Gulf and its tributary cirques form the largest cirque in the White Mountains.Daniell and Smith, p. 11. South of the Great Gulf is Huntington Ravine, with a rocky, precipitous headwall renowned for its rock and ice climbing.Randall, Peter. Mount Washington: A Guide and Short History. University Press of New England, 1974. . p. 138. The slope then dips into the Ravine of Raymond Cataract, a non-glacial "V-shaped" valley with a notable waterfall. After this comes Tuckerman Ravine, with a uniform, smoother headwall that is known for its high-quality skiing.Randall, p. 131. After passing the Gulf of Slides, a smaller and lesser-known cirque, the notch opens up and continues until Jackson.

The eastern slope of the notch consists of the Wildcat and Carter-Moriah Ranges, slightly lower than the Presidential Range to the west. The Wildcat Range consists of five peaks, named A, B, C, D, and E from northeast to southwest in order of height.Daniell and Smith, p. 384. Wildcat A is the highest, at . From the main ridge, the slopes drop very steeply, but not precipitously, to the floor of the notch. The Wildcat Mountain Ski Area occupies the western slopes of Wildcat up to the col between D and E peaks. History of Wildcat Mountain Ski Resort. Wildcat Mountain. 2001. Retrieved 9 September 2006 As the notch rounds E peak, the slope becomes extremely steep, and Wildcat Ridge begins to drop to the end of the notch.

The Carter-Moriah Range lies to the north of Wildcat Ridge, forming the eastern side of Pinkham Notch all the way to the Androscoggin River.Daniell and Smith, p. 384–385. From south to north, the peaks overlooking the notch are Carter Dome (4,832 ft / 1,473 m), Mount Hight (4,675 ft / 1,425 m), South Carter Mountain (4,420 ft / 1,347 m), Middle Carter Mountain (4,600 ft / 1,402 m), North Carter Mountain (4,530 ft / 1,381 m), Imp Mountain (3,720 ft / 1,134 m), and Mount Moriah (4,049 ft / 1,234 m).Daniell and Smith, p. 385.

Climate The weather in the area varies by altitude and the orientation of the land. A weather station has operated at around 2,000 feet since 1930.

Climate

According to the Köppen Climate Classification system, Pinkham Notch has a humid continental climate, abbreviated "Dfb" on climate maps. The hottest temperature recorded in Pinkham Notch was on July 20, 1982, while the coldest temperature recorded was on February 16, 1943.

Environment The climate, and as a result, the flora and fauna, of Pinkham Notch varies greatly with elevation. As elevations increase on the walls of the notch, climate and ecosystems change to those of increasingly northern occurrence. Biomes range from a low-elevation northern hardwood forest at the base of Mount Washington to alpine-Arctic vegetation near the summit comparable to vegetation found at the latitude of Labrador.Stier, Maggie and McAdow, Ron. Into the Mountains. AMC Books, 1995. . p. 240.

Below 2500 ft. — northern hardwood forest

The lowest elevations of Pinkham Notch are occupied by a northern hardwood forest. This forest type is primarily deciduous and consists mostly of sugar maple, American beech, and yellow birch.Slack, Nancy G. and Bell, Alison W. Field Guide to the New England Alpine Summits. AMC Books, 1995. . pp. 19–21. There is also a proliferation of understory and forest floor plants; common examples include wild sarsaparilla, painted trillium, hobblebush, and Indian cucumber-root.Slack and Bell, p. 20.

The northern hardwood forest also contains the greatest diversity of animal life in the notch.Slack and Bell, p. 21. Mammals include chipmunks, raccoons, white-tailed deer, black bears, and moose. There are also a large number of birds in this forest; frequently seen are red-eyed vireos, hermit thrushes, and ovenbirds. Amphibians are also found in the northern hardwood forest. Red efts, the terrestrial stage of development for the red-spotted newt, congregate in large numbers after heavy rains; also present are American toads, spring peepers, and wood frogs.

At around , species from higher forest zones begin to mix with the northern hardwoods in what is known as the "transition zone". As elevation within this zone increases, species from the lower hardwood forest begin to drop out. By , yellow birch is the only deciduous species that remains, and the forest becomes a spruce-fir forest.Slack and Bell, p. 15.

2500 ft. to 4000 ft. — spruce/fir forest As elevation increases, the forest is subjected to colder temperatures, increased moisture, and acidic, infertile soils. As a result, conifers, or "softwoods" become the dominant species. Two trees, red spruce and balsam fir, are present throughout this zone, with paper birch, striped maple and mountain ash present in its lower levels.Slack and Bell, pp. 22–24. Like the hardwood forest below it, the spruce-fir forest also holds understory plants; commonly found are wood sorrel, Indian pipes, Canada mayflowers, and bluebead lilies. Fungi are also common in the moist environment.

Most of the animals in the spruce-fir forest have ranges that extend into the balsam fir forest higher up.Slack and Bell 24–25 Warblers are abundant; more than ten species exist in this forest type. Other common birds include brown-capped chickadees, spruce grouse, and yellow-capped woodpeckers. Mammals include the red squirrel and the pine marten.

4000 ft. to timberline — balsam fir forest As elevation continues to increase, only the hardiest trees remain in the forest, which is composed almost exclusively of balsam fir.Slack and Bell, pp. 24–29. Most of the understory plants and animals from the upper spruce-fir zone, however, can be found in this forest. Moisture causes nutrients to be stripped from the soil and brought to lower elevations, and decomposition takes place at a rate that is too slow to replenish them.

In the upper reaches of the balsam fir zone, winds and temperatures are extreme enough to force the trees into stunted, "bonsai-like" shapes. Known as krummholz, from the German word for "crooked wood", trees in this area are often bent into bizarre shapes by the combined effects of wind, temperature, and airborne ice particles. Branches that are perpendicular to the prevailing winds are often killed, leaving "flag trees" that point in the direction of the wind. Eventually, conditions become extreme enough to prevent any tree growth; the elevation at which this occurs is known as tree line, and usually occurs at around 4,500 ft (1,400 m) in the White Mountains, depending on wind exposure.Monkman, Jerry and Monkman, Marcy. Discover the White Mountains of New Hampshire. AMC Books, 2001.

Above timberline — alpine zone On the highest slopes of the west wall of the notch, trees are unable to grow, and an "alpine zone" of alpine-Arctic vegetation exists.Slack and Bell, pp. 30–32. Vegetation in this zone tends to be lichens, sedges or small, low-lying plants that can resist the constant exposure to the wind. Most plants in this area are perennial; the growing season is far too short to allow for annuals.

Alpine plants usually occur in communities spaced between barren talus slopes. Cushion-shaped Diapensia lapponica usually grows in communities in the windiest areas, and in less exposed sites sedge, heath, snowbank, and alpine bog communities can be found.Slack and Bell, pp. 69–78.

History Pinkham Notch was originally a riverine, "V-shaped" valley until the Laurentide Ice Sheet shaped it into its current form, a "U-shaped" valley.Randall, p. 115. This shaping occurred during the Wisconsinian Ice Age, 25–50,000 years ago.Alden, Peter and Cassie, Brian National Audubon Society Field Guide to New England. Chanticlear Press, 1998. . pp 18–19. The geology of the region became greatly altered by this event; much of the weaker rock was stripped from the region, leaving only highly-resistant mica schist. As the glaciers retreated, a layer of glacial till was deposited, including several glacial erratics.Randall, pp. 115–116. A notable glacial erratic in the area is Mount Washington's Glen Boulder.Daniell and Smith 29

The notch first appears in recorded history in 1784, when an expedition led by Jeremy Belknap camped in the notch before ascending to the summit of Mount Washington through Huntington Ravine.Stier and McAdow, p. 248. Pinkham Notch was far more isolated than neighboring Crawford Notch; as a result, the first settler of Pinkham Notch came in 1827, 43 years after habitation of Crawford Notch. The first settler, Hayes Copp, built a homestead in the then-uninhabited area, near where the Dolly Copp campground stands today. Copp and his wife lived alone in the wilderness until Daniel Pinkham completed the first road through the notch between in 1836, finally providing a link between the Copp homestead and civilization.Randall, p. 9. In 1851, a railroad was built to Gorham, and a hotel, the Glen House, was constructed to accommodate passengers.Randall, p. 12. Mount Washington was the main attraction in the area; a bridle path was constructed from the Glen House to hotels on the summit, which was later improved into what would become the Mount Washington Auto Road. Completion of the road in 1861 led to a massive increase in tourism.Randall, p. 15.

Meanwhile, logging began in the Pinkham area. After almost total deforestation of the White Mountain region, the White Mountain National Forest was created in 1911, and the Mount Washington area was added to the national forest in 1914.Randall, p. 16. With the preservation of the area, emphasis shifted from logging to recreation. The Appalachian Mountain Club converted a logging camp near the height-of-land into what is now the Pinkham Notch Visitor Center in 1921.Randall, p. 142. The Appalachian Trail was built through the visitor center, making it an important trailhead for ascents of Mount Washington. Meanwhile, ski trails began to be constructed by the Civilian Conservation Corps on Wildcat Mountain, and the ski resort was opened in 1958.

Recreation Pinkham Notch is easily accessible by New Hampshire Route 16. Numerous opportunities for recreation exist in the area.

Hiking