EP 1135.01

Project Title:

Enhancing Early Stand Growth through the use of Vegetation Management - 15 Year Post-treatment Results

Reference Numbers:

MOFR17100-20 / EP 1135.01 FSP M075004

Project Start/End Dates:

1991-Ongoing

Keywords:

growth and yield modelling, vegetation management, free growing, site productivity, herbicides, glyphosate, cutting treatments, repeated manual brushing, Tree and Stand Simulator (TASS), stand development modeling, mixed-shrub competition, Southern Interior Forest RegionTop

MFR Initiatives Supported:

timber supply, vegetation management practices, mountain pine beetle (MPB) mitigation, industry competitiveness, forest inventory, spruce density management

BEC Units:

ICH

Location:

Soards Creek, Mica BC. Revelstoke Forest District

Objectives:

  • To support cost effective, stand establishment vegetation management practices that may mitigate Mountain Pine Beetle (MPB) losses through improving timber growth and yield;
  • To compare the long-term effectiveness of single and repeated manual cutting treatments and a single herbicide glyphosate application to control mixed-shrub vegetation and improve growing conditions for Engelmann spruce seedlings;
  • To explore the long-term impacts of vegetation control treatments on the dynamics of the vegetation community;
  • To model the long-term growth and yield implications of manual cutting and herbicide treatments.Top

Summary:

Vegetation management treatments are often used to ensure that young conifer stands achieve free-growing requirements. A study area near Mica Creek was established in 1991 to examine the effects of vegetation control treatments on the survivorship and growth of Engelmann spruce seedlings in a mixed-shrub community. Vegetation control treatments included single and repeated manual cutting, and single application of the herbicide glyphosate. Seedling and vegetation measurements were collected in year 0 (pre-treatment), 1, 2, 3, 4, 5, 7, 10, and 15 years after planting. Treatment significantly increased height and groundline diameter for Engelmann spruce from the third through the seventh year but not after year ten. Treatments significantly improved spruce survival, but did not have any significant effect on plant species richness, diversity, or percent cover after year ten. Results from these measurements were entered into TASS to project growth and rotation ages for the spruce (Harper et al. 2008).

Related Publications:

Biring, B.S., P.G. Comeau and P. Fielder. 2003. Long-term effects of vegetation control treatments for release of Engelmann spruce from a mixed-shrub community in Southern British Columbia. Ann. For. Sci. 60: 681–690.[link] 

Biring, B.S., H.K. Yearsley, and W.J. Hays-Byl. 2001. Ten-year responses of white spruce and associated vegetation after glyphosate treatment at Tsilcoh River. B.C. Min. For., Res. Br., Victoria, B.C. Exten. Note 55.

Comeau P.G., Biring B.S., Harper G.J. 2000. Effectiveness of repeated manual cutting and glyphosate for release of Engelmann spruce from mixed-shrub herb vegetation, West. J. Appl. For. 15(3): 154-162. [link] 

Comeau P.G., Light attenuation by thimbleberry-fireweed communities in the ICH zone and its potential effects on conifer growth.  1988.  In: Hamilton E., Watts S. (Eds.), Vegetation Competition and Responses: Proc. 3rd Ann. Veg. Manage. Work., Feb. 15-17, 1988, Vancouver, B.C., For Can. and B.C. Min. For., Victoria, B.C., FRDA Rep. 026, pp. 5-7.

Comeau P.G., Biring B.S., Harper G.J.  1999.  Conifer response to brushing treatments: A summary on British Columbia, B.C. Min. of For., Res. Br., Victoria. B.C. Exten. Note 41.

Harper, G., K. Polsson and J. Goudie.  2008.  Modelling vegetation management treatments with the Tree and Stand Simulator.  For. Chron. 84(1): 53-59. [link]Top

Click to see larger picture.   Click to see larger picture.
Figure 1: Engelmann spruce seedling planted June 1991 at the Mica Creek Study Area   Figure 2: Mixed-shrub competition on the Mica study area in 1996
     
Click to see larger picture.   Click to see larger picture.
Figure 3: Plot in year 7, showing vegetation reduction treatment after three summers of manual brushing.   Figure 4: Plot in year 15, showing vegetation reduction treatment after three summers (3 ×) of manual brushing.
         
Click to see larger picture.   Click to see larger picture.   Click to see larger picture.
Figure 5: Plot in year 15, showing vegetation reduction treatment after two springs and two summers (4 ×) of manual brushing.   Figure 6: Plot in year 15, showing vegetation reduction treatment after three springs and three summers (6 ×) of manual brushing.   Figure 7: Plot in year 15, showing vegetation reduction treatment of one application of glyphosate.

Contact Person: George Harper, Research Scientist, Stand Development
Email: George.Harper@gov.bc.ca
 

Please direct questions regarding webpage to For.Prodres@gov.bc.ca
Updated April 2008