Columbia Mountains Institute of Applied Ecology

A study of plant community structure and a reclamation evaluation of disturbed  subalpine sites in Glacier National Park

Tamara Lamb, MS.
Mount Revelstoke/Glacier National Park

 

From 1984 to 1989, Canadian Pacific Railway constructed 34 km of track and tunnels through Glacier National Park in an effort to increase its operating capacity and to reduce bottlenecks occurring westbound on the original track. The disturbance to the park was significant and CPR was required to reclaim where possible. The reclamation plan involved site preparation, seeding, fertilizing, and planting seven separate sites all occurring in the Interior Cedar Hemlock biogeoclimatic zone. The objective of the reclamation was to develop a self-sustaining vegetation cover that was compatible with the naturally occurring vegetation in the area (Polster Environmental Services, 1990). The seed mix consisted of introduced species and was designed to be a temporary cover that would stabilize the sites until native species invaded or established on the sites. Native trees and shrubs were planted on the site to speed up the successional establishment of a native vegetation community.

A study was conducted in 1996 with the following objectives: to assess plant community structure in a subalpine forest ecosystem 10 years after the CPR disturbance; and to assess the success of revegetation based on the criteria agreed upon by Parks Canada and Canadian Pacific Railway.

The vegetation in one quarter of the total area in seven separate sites were sampled. Vegetation plots were measured for species abundance, species richness, percentage canopy cover and plant vigour. Vegetation transects were laid outward from the disturbance to detect any effects from the adjacent undisturbed plant community. After analysis of the plot data, the following conclusions have been drawn:

1. Ten years after reclamation the sites continue to be dominated by the seeded introduced species particularly Festuca rubra, Dactylis gomerata, Phleum pratense and Medicago sativa. Further use of these species for reclamation of similar subalpine sites in not recommended if the end goal is a native plant community.
2. Planting shrub and tree species is a useful tool for establishing woody species on a site dominated by introduced grass and forb species.
3. Overall, the reclamation obligations of CPR have been met. These obligations include a minimum plant density of 10 plants per square yard, an average canopy cover of 80% and a minimum survival rate of 75% for planted woody species.

Publications and Reports

Lamb, T. 1998. A Study of Plant Community Structure and a Reclamation Evaluation of Disturbed Subalpine sites in Glacier National Park, British Columbia. MS. Thesis. University of Alberta. 89 pp.

Lamb, T., Naeth, A. and Rothwell, R. 1998. Reclamation Evaluation of the Rogers Pass Project. Prepared for Parks Canada and Canadian Pacific Railway. 44 pp.

Project support was from: Parks Canada (Mount Revelstoke and Glacier National Parks) and Canadian Pacific Railway.