Natural Communities of NH -- Photo Guide

Subalpine cold-air talus shrubland  (S1)


(formerly subalpine cold-air talus barren)

Subalpine cold-air talus shrubland is a rare community primarily found at the base of large talus slopes in the White Mountains. It can also be found in deep, shaded ravines such as Ice Gulch. Cool air emerges from beneath boulders where ice lingers into late summer. The cold micro-environment has a profound effect on vegetation, creating conditions suitable for subalpine plants otherwise restricted to higher elevation mountaintops. Dwarf spruce trees typically reach less than five feet in height, and a short layer of evergreen shrubs grows on the surface of talus boulders. Montane mosses and lichens are common.

Characteristic vegetation:
Characteristic dwarf trees include red spruce (Picea rubens) and black spruce (Picea mariana), with lesser amounts of heartleaf birch (Betula cordifolia), American mountain ash (Sorbus americana), and balsam fir (Abies balsamea). The sparse and stunted tree canopy is generally less than 10–20 ft. tall.

The shrub layer is well-developed and comprised of short or ground-hugging species ranging in height from less than 20 cm to 50 cm or more in some areas. Shrubs
include alpine bilberry (Vaccinium uliginosum), purple crowberry (Empetrum atropurpureum), Labrador tea (Ledum groenlandicum), sheep laurel (Kalmia angustifolia), mountain cranberry (Vaccinium vitis-idaea), velvet-leaf blueberry (Vaccinium myrtilloides), and lowbush blueberry (V. angustifolium). Infrequent species include rhodora (Rhododendron canadense) and creeping snowberry (Gaultheria hispidula). Herbaceous species are notably sparse or absent. Montane lichens are common.


Good examples of this community can be found below Cannon Cliff (Franconia Notch), Ice Gulch (Randolph), Carter Notch (Beans Purchase), King and Castle Ravines in the Presidential Range.

Subalpine cold-air talus shrubland communities often occur as part of a larger montane acidic talus system.


Subalpine cold-air talus shrubland in Ice Gulch (photo by Ben Kimball for the NH Natural Heritage Bureau)
Subalpine cold-air talus shrubland in Ice Gulch (photo by Ben Kimball)

Subalpine cold-air talus shrubland at the base of Cannon Cliff (photo by Dan Sperduto for the NH Natural Heritage Bureau)
Subalpine cold-air talus shrubland at the base of Cannon Cliff (photo by Dan Sperduto)

Subalpine cold-air talus shrubland at The Ramparts (photo by Dan Sperduto)
Subalpine cold-air talus shrubland at The Ramparts
in Carter Notch (photo by Dan Sperduto)



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