Natural Community Systems -- Photo Guide

Alpine/subalpine bog system

Alpine/subalpine bog system at Star Lake in the Presidential Range (photo by Ben Kimball for the NH Natural Heritage Bureau)
alpine/subalpine bog system at Star Lake in the Presidential Range (photo by Ben Kimball)

Alpine/subalpine bog system on Shelburne-Moriah Mtn. (photo by Ben Kimball for the NH Natural Heritage Bureau)
alpine/subalpine bog system on Shelburne-Moriah Mtn. (photo by Ben Kimball)

hikers traverse an alpine/subalpine bog system on Mt. Success in NH (photo by Ben Kimball for the NH Natural Heritage Bureau)
hikers traverse an alpine/subalpine bog system on Mt. Success in NH (photo by Ben Kimball)

  

Description:  This system includes sloping and level peatlands that occur in the subalpine and alpine zone from 2,9004,900 ft. elevation in the White Mountains.  They are small (less than an acre to several acres max.) and occur in concavities on ridges, and on moderate to steep slopes over bedrock where some combination of limited drainage, high precipitation amounts (partly due to cloud-intercept in the subalpine climate), late-melting snowpacks, and self-maintaining Sphagnum (peat moss) mats contribute to peat accumulation.  Sloping peatlands are largely restricted to northern climates, and in New Hampshire they are restricted to the White Mountains and the northern part of the state.  Here the cold wet climate and low evapotranspiration combine to allow peat to accumulate on sloping ground.  Alpine/subalpine bog systems are dominated primarily by lowland bog plants found in poor level fen/bog systems, but are distinguished from them by alpine and subalpine plants.

Alpine/subalpine bog systems contain one or more of three peatland community types (see below).  While sloping peatlands are a unique characteristic of some alpine/subalpine peatlands, degree of wetness appears to be a more important determinant of species composition and natural community type than slope per se.  Many examples of this system contain both alpine/subalpine bogs (very poorly drained concavities and occasionally on slopes) and wooded subalpine bog/heath snowbanks (sloping to level ground, less wet, more black spruce and balsam fir, but still with thick, peaty organic soils).  The wet bogs have several wet-site bog species that are absent in wooded subalpine bog/heath snowbanks.  The wooded subalpine bog/heath snowbanks occur as a border zone around wetter bogs or in association with late melting snowbank areas, and have more black spruce and balsam fir.  Subalpine sloping fens are boggy peat mats on the brow of some high elevation cliffs that are subject to sloughing off the cliff-edge, and contain the rare Calamagrostis pickeringii (Pickering's reed bent-grass).


Diagnostic natural communities:

      • Alpine/subalpine bog (S1)

      • Wooded subalpine bog/heath snowbank (S1S2)

      • Subalpine sloping fen (S1)


Landscape settings: concavities on ridges and on moderate to steep slopes over bedrock in subalpine and alpine zones

Soils: poorly to moderately well decomposed peat soils over bedrock, generally less than 75 cm deep; oligotrophic; pHs less than 4.0; topogenous to soligenous water sources

Spatial pattern: small patch (<15 ac); circular to irregular shape; concentric zonation or uniform

Physiognomy: dwarf shrub and moss/liverwort lawns

Distribution: restricted to the White Mountains


Characteristic species: Species characteristic of alpine bogs but absent or rare in poor level fen/bogs of lowlands:

Alpine/subalpine bog
   Trees – absent or sparse 

   
Dwarf shrubs 
      Alpine/subalpine indicators:
      Vaccinium uliginosum (alpine bilberry)
      Empetrum nigrum (black crowberry)
      Rubus chamaemorus (baked apple berry)
      Vaccinium vitis-idaea (mountain cranberry)

   Other dwarf shrubs:
      Vaccinium oxycoccos (small cranberry) 
      Kalmia polifolia (bog laurel)
      Ledum groenlandicum (Labrador tea) 
      Chamaedaphne calyculata (leatherleaf) -- >10%
      Kalmia angustifolia (sheep laurel) -- <10%

   
Herbs
      Eriophorum vaginatum (hare's-tail)
      Scirpus cespitosus (tussock bulrush)

   
Bryophytes and lichens
      Peat mosses -- constant & abundant
      Sphagnum fuscum (peat moss)
      Sphagnum capillifolium (peat moss)
      Cetraria islandica (lichen)
      Cladina rangiferina (lichen)

Wooded subalpine bog/heath snowbank:   
   
Trees – prominent 
      Picea mariana (black spruce)
      Abies balsamea (balsam fir)

   
Dwarf shrubs
      Alpine/subalpine indicators:
      Vaccinium uliginosum (alpine bilberry)
      Empetrum nigrum (black crowberry)
      Rubus chamaemorus (baked apple berry) -- mostly absent
      Vaccinium vitis-idaea (mountain cranberry)
      Other dwarf shrubs:
      Ledum groenlandicum (Labrador tea) 
      Chamaedaphne calyculata (leatherleaf) -- <10%
      Kalmia angustifolia (sheep laurel)

   
Bryophytes and lichens
      Peat mosses -- less frequent & abundant
      Cetraria islandica (lichen)
      Cladina rangiferina (lichen)


Associated natural community systems:  In parts of the White Mountains alpine/subalpine bog systems form a mosaic with subalpine heath/krummholz systems that have collectively been referred to as “heath balds.”  These heath balds occur mostly below 4,000 ft. elevation on flat to gently sloping ridgetops of the Mahoosuc, Carter-Moriah, and Baldface Ranges.  Smaller examples are found in several other scattered locations.  Otherwise alpine/subalpine bog systems are found either within the higher elevation alpine tundra system mosaic in the Presidential Range, or embedded as patches within high-elevation spruce-fir forest systems.



back to NH Natural Community Systems list