Ponderosa Pine Biogeoclimatic zone (PP)



Ecoregions: Southern Interior
Elevations: 335-900m
Latitudes: 49-51 degrees
 
Description:

  • Warmest and driest forest zone.
  • Narrow band in the driest and warmest valleys of the Southern Interior (Fraser/Thompson, Okanagan/Similkameen, Keetle, Pend d'Oreille, Columbia)
  • Grades to BB at lower elevations and to the IDF at higher elevations
  • Ponderosa pine the dominant tree in open savannah-like stands, with Douglas-fir common on cooler and moiser sites
  • Understory characterized by abundant grasses such as bluebunch wheatgrass and rough fescues
  • Frequent ground fires create and maintain stand structure
  • Important habitat for California bighorn sheep, burrowing owl, grouse and white-tailed deer>
Representative Species:
Drier phase
 

Trees

  Pinus ponderosa (ponderosa pine)
 

Shrubs

  Amelanchier alnifolia (saskatoon)
  Artemisia tridentata (big sage)
  A. frigida (pasture sage)
  Chrysothamnus nauseosus (rabbit brush)
 

Forbs and Grasses

  Festuca saximontana (Rocky mtn. fescue)
  Festuca idahoensis (Idaho fescue)
  Crepis atrabarba (slender hawksbeard)
  Astragalis miser (timber milk-vetch)
  Agropyron spicatum (bluebunch wheatgrass)
  Balsamorhiza sagittata (balsamroot)
  Achillea millifolium (yarrow)
 
Wetter Phase
 

Trees

  Pinus ponderosa (ponderosa pine)
  Pseudotsuga menziesii (Douglas-fir)
 

Shrubs

  Amelanchier alnifolia (saskatoon)
  Sympohoricarpos albus (snowberry)
  Rosa spp. (roses)
  Acer glabrum (Douglas maple)
  Mahonia aquifolium (tall Oregon-grape)
  Cornus stolonifera (Red-osier dogwood)
 

Forbs and Grasses

  Agropyron spicatum (bluebunch wheatgrass)
  Koeleria macrantha (June grass)
  Poa sandbergii (Sandberg's bluegrass)
  Antenaria dimorpha (pussytoes)
 
Potential Restoration Species:
Drier phase
 

Trees

  Pinus ponderosa (ponderosa pine)
 

Shrubs

  Amelanchier alnifolia (saskatoon)
  Artemisia tridentata (big sage)
  A. frigida (pasture sage)
  Chrysothamnus nauseosus (rabbit brush)
 

Forbs and Grasses

  Aristida longiseta (red three-awn)
  Balsamorhiza sagittata (balsamroot)
  Festuca saximontana (Rocky mtn. fescue)
  Festuca idahoensis (Idaho fescue)
  Agropyron spicatum (bluebunch wheatgrass)
 
Wetter Phase
 

Trees

  Pinus ponderosa (ponderosa pine)
  Pseudotsuga menziesii (Douglas-fir)
 

Shrubs

  Amelanchier alnifolia (saskatoon)
  Sympohoricarpos albus (snowberry)
  Rosa spp. (roses)
  Acer glabrum (Douglas maple)
  Mahonia aquifolium (tall Oregon-grape)
  Cornus stolonifera (Red-osier dogwood)
 

Forbs and Grasses

  Agropyron spicatum (bluebunch wheatgrass)
  Distichlis stricta (alkaline saltgrass)
  Smilacina stellata (star flowered false Solomon's seal)
 
Meidinger, D. and Pojar, J. 1991. Ecosystems of British Columbia. British Columbia Ministry of Forests. 330 pp. http://www.for.gov.bc.ca/hfd/pubs/Docs/Srs/SRseries.htm