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BC Conservation Data Centre: Conservation Status Report

Pinus ponderosa / Pseudoroegneria spicata - Festuca campestris
ponderosa pine / bluebunch wheatgrass - rough fescue

 
Scientific Name: Pinus ponderosa / Pseudoroegneria spicata - Festuca campestris
English Name: ponderosa pine / bluebunch wheatgrass - rough fescue
   
Provincial Status Summary
Status: S2
Date Status Assigned: June 19, 2013
Date Last Reviewed: June 19, 2013
Reasons: This moist woodland ecological community was formerly relatively widespread and formed the matrix ecosystem. It now occupies a very small proportion of its small range. Analysis of Terrestrial Ecosystem Mapping data for one-third of the range (TEM: South Okanagan 2009, Central Okanagan 2009, TFL 15 1999, Lake Country 2005) suggests that there has been a substantial decline over the long term. It continues to be threatened primarily by invasion of alien species, conversion to agriculture, livestock grazing and residential development. Fire supression, and recreational activities generally have both lower scope and severity. The change in conservation status rank is based on information from Terrestrial Ecosystem Mapping.
 
Range
Range Extent: D = 1,000-5,000 square km
Range Extent Estimate (km2): 2766
Biogeoclimatic Unit: BGxw1/05
PPxh1/05
PPxh2/01
Range Extent Comments: The range extent estimate of this ecological community is based on Version 9 of the Biogeclimatic Ecosystem Classification (BEC) map (B.C. Ministry of Forests, Lands, and Natural Resource Operations. 2014). It occurs in valleys in the south-central interior of B.C. It is found along the Thompson R. from Kamloops to Lytton, the North Thompson R. to south of McClure, Paul Ck. from the North Thompson R. to half way to Paul Lk., the South Thompson river to just south of Chase, the Nicola R. from the Thompson R. to Nicola Lk., Stumplake Ck. from Nicola Lk. to Stump Lk., the Coldwater R. from the Nicola R. to just south of Kwinshatin Ck., the Bonaparte R. from the Thompson R. to Maiden Ck. (between Cache Ck. and Clinton), parts of Hat Ck. from Bonaparte R. to Medicine Ck., the Fraser R. from Pavillion Ck. to south of Lytton, and the Bridge R. from the confluence with the Yalakam R. to the Fraser R. It is also found in the Okanagan Valley from the north end of Skaha Lake to the U.S. border, along the Similkameen River from Keremeos to the U.S. border, and around Princeton (BEC map Version 9; Lloyd et al. 1990).
Area of Occupancy (km2): F = 100-500 km²
Area of Occupancy Comments: This ecological community was formerly relatively widely distributed within its small range, but much of it is now degraded. Although spatial distribution varies, the majority occurs as a matrix. Based on Sensitive Ecosystems Inventory (SEI) and Terrestrial Ecosystem Mapping (TEM), this community occupies about 54 km2 or about 6% of the mapped area which is only one-third of the total range (TEM: South Okanagan 2009, Central Okanagan 2009, TFL 15 1999, Lake Country 2005). Based on extrapolation from the mapped area, there are an estimated 162 km2 for the whole range.
Spatial Pattern:
 
Occurrences
Number of Occurrences: U = Unknown
Number of Occurrences with Good Viability / Ecological Integrity: U = Unknown
Comments: Few sites in excellent or good condition.
 
Threats (to population, occurrences, or area affected)
Degree of Threat: B = High
Comments: This moderately moist woodland is mainly threatened by continuing invasion by alien species (large scope, moderate severity), while conversion to agriculture and residential development have a lower scope, but serious and extreme severity, respectively. Livestock grazing and fire supression generally have both lower scope and severity.
 
Trend (in population, range, area occupied, and/or condition of occurrences)
Short-Term Trend: U = Unknown
Comments: Insufficient information available.
Long-Term Trend: EH = Decline of <50% to increase of <25%
Comments: Terrestrial Ecosystem Mapping (TEM: South Okanagan 2009, Central Okanagan 2009, TFL 15 1999, Lake Country 2005) for one third of the range of this ecosystem, shows that there is 15% less in mature and old seral stages combined, compared to the recommended seral stage distribution in the Biodiversity Guidebook (Biodiversity Guidebook 1995). This suggests a decline over the long term (> 40 years), but may not accurately represent trends for the ecosystem because the third of the range that is mapped is geographically separated and subject to somewhat different threats (Yearsley et al. 2013).
 
Other Factors
Intrinsic Vulnerability: B=Moderately vulnerable
Comments: These mesic woodlands with fescue generally have few limitations for tree establishment, so they are dependent on wildfire as a natural disturbance regime to maintain the open canopy and grassland understory, and are therefore vulnerable to fire suppression. Ingrowth of more trees can then make them more susceptible to severe, stand-replacing fires (K. Iverson pers. comm.).
Environmental Specificity: D=Broad. Generalist or community with all key requirements common.
Comments: This ecological community occurs primarily on mesic sites on generally gentle mid to lower slopes with medium to coarse-textured soils over morainal blankets or glaciofluvial or glaciolacustrine valley terraces.
Other Rank Considerations:
 
Information Gaps
Research Needs: Research on the effects of climate change.
Inventory Needs: Inventory in parts of the range, and occurrence mapping from Terrestrial Ecosystem Mapping (TEM), is needed.
 
Stewardship
Protection:
Management:
 
Version
Author: Yearsley, H.K. and C.M. Cadrin
Date: December 13, 2013
 
References
B.C. Ministry of Forests, Lands, and Natural Resource Operations. Biogeoclimatic Ecosystem Classification (BEC) Map, WHSE_FOREST_VEGETATION.BEC_BIOGEOCLIMATIC_POLY [ESRI ArcSDE format]. Version 9. Ministry of Forests, Lands, and Natural Resource Operations, Forest Analysis and Inventory Branch, Victoria, B.C. Updated Regularly.
Biodiversity Guidebook. 1995. Forest Practices Code of British Columbia. B.C. Minist. For. and B.C. Minist. Environ., Victoria B.C. ix + 99p.
Flynn, Samantha. 2000. Plant Association Status Ranking 1999-2000. Access Digital Database. BC Ministry of Environment, Conservation Data Centre. Victoria, BC.
Lloyd, D., K. Angove, G. Hope, and C. Thompson. 1990. A guide to site identification and interpretation for the Kamloops Forest Region. B.C. Minist. For., Res. Branch, Victoria, B.C. Land Manage. Handb. No. 23. 399pp.
Meidinger, D. et. al. 2001. Unpublished notes from rare plant community ranking review, March, 2001.
Terrestrial Ecosystem Mapping [TEM] of the Central Okanagan Valley: updated Mar. 2009c. Prepared for Okanagan Collaborative Conservation program by A. Haney and K. Iverson. 1:20,000 spatial data.
Terrestrial Ecosystem Mapping [TEM] of the Lake Country Study Area. 2005b. February 2006. K. Iverson and P. Uunila. 1:20,000 spatial data.
Terrestrial Ecosystem Mapping [TEM] of the South Okanagan and lower Similkameen Valley: refined and updated 2009b. K. Iverson and A. Haney. 1:20,000 spatial data.
Terrestrial Ecosystem Mapping [TEM] of Weyerhaeuser Canada Ltd., Tree Farm License 15. 1999d. Prepared for Weyerhaeuser Canada Ltd., Okanagan Falls in partnership with FRBC and the Ministry of Forests, Kamloops, B.C., by Bruhjell, D. and S. Robertson 1:20 000 spatial data.
 

Please visit the website Conservation Status Ranks for information on how the CDC determines conservation status ranks. For global conservation status reports and ranks, please visit the NatureServe website http://www.natureserve.org/.

Suggested Citation:

B.C. Conservation Data Centre. 2013. Conservation Status Report: Pinus ponderosa / Pseudoroegneria spicata - Festuca campestris. B.C. Minist. of Environment. Available: https://a100.gov.bc.ca/pub/eswp/ (accessed Feb 20, 2025).