page_title: Mount Monadnock
section_title: Bio-geography, ecology, and geology
hierarchical_section_title: Mount Monadnock / Bio-geography, ecology, and geology
caption_attribution_description: English: Billings Fold, Mount Monadnock, NH
context_page_description: Mount Monadnock, or Grand Monadnock, is a 3,165 ft mountain in the towns of Jaffrey and Dublin, New Hampshire. It is the most prominent mountain peak in southern New Hampshire and is the highest point in Cheshire County. It lies 38 miles southwest of Concord and 62 miles northwest of Boston. At 3,165 feet, Mount Monadnock is nearly 1,000 feet higher than any other mountain peak within 30 miles and rises 2,000 feet above the surrounding landscape. It is known for being featured in the writings of Ralph Waldo Emerson and Henry David Thoreau.
  Mt. Monadnock has long been cited as one of the most frequently climbed mountains in the world. Monadnock's bare, isolated, and rocky summit provides expansive views. It bears a number of hiking trails, including the 110-mile Metacomet-Monadnock Trail and the 50-mile Monadnock-Sunapee Greenway. The summit is barren largely because of fires set by early settlers. The first major fire, set in 1800 to clear the lower slopes for pasture, swept through the stands of virgin red spruce on the summit and flanks of the mountain. Between 1810 and 1820, local farmers, who believed that wolves were denning in the blowdowns, set fire to the mountain again.
context_section_description: Due to fires in the early 19th century which burned a majority of the top 300 feet (90 m) around the summit, there is little soil cover on the peak and surrounding uplands. Although the mountain has recovered to the degree that its landscape appears natural, Mount Monadnock is an example of a mountain which has an artificial tree line, occurring well below the climatic tree line of similar mountains in the region.
  From the base to the summit, floral species diminish with increasingly shallow soil levels. The summit is home to many different specialized sub-alpine species which can retain moisture for long periods of time. Alpine and sub-alpine species include mountain ash, cotton grass, sheep laurel, mountain sandwort, and the mountain cranberry. Krummholz, trees stunted by harsh weather, are found on Mount Monadnock, as are several alpine bogs. Lower elevations on Mount Monadnock are clad in northern hardwood forest species; middle elevations support stands of red spruce. Before the fires, Mount Monadnock was totally covered in a red spruce forest. Since the summit has been barren of soil cover, red spruce have been slowly ascending back towards the top in a process known as ecological succession.
  The mountain is largely composed of 400-million-year-old schist and quartzite rock primarily associated with the Devonian Littleton Formation, which extends south into Massachusetts and north into the White Mountains. At lower elevations on the mountain, and stratigraphically below the Littleton Formation, the bedrock is from the Silurian period, consisting of Rangeley Formation schists, Perry Mountain Formation quartzites, the Francestown Formation granulite, and the Warner Formation granulite. Structurally, the mountain is part of an overturned syncline – called a fold nappe – that was caused by the compressional forces of the Acadian orogeny. Dramatic small- to medium-scale metamorphic folds are visible on many of the rock faces of the mountain, including the famous Billings Fold (a recumbent syncline found about 450 feet (140 m) west of the summit), shown in the 1942 edition of Marland P. Billings' Structural Geology. In addition to impressive folds, the Devonian Littleton Formation shows large pseudomorphs of sillimanite after andalusite that occur as 4-inch-long (102 mm) "turkey tracks".
caption: The Billings fold in quartzite and schist of the Devonian Littleton Formation
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