Objectives:

The project was established in 1952-53 in order to determine the effects of different intensities of treatment upon the stand, and to observe the reaction of a non-uniform Engelmann spruce understory to the treatments.

Experimental Design:

Treatments

• The stand is the result of natural regeneration following burning around 1895.
• The average age of the stand was 53 years in 1953.
• The site is fully stocked with lodgepole pine. Western larch veterans and Engelmann spruce understory are irregularly distributed throughout the stand.
• Treatments consisted of five thinnings (2197, 1682, 1193, 747 and 420 stems/ha.) and an unthinned control.

Layout:

• Two replications of the six treatments were used, for a total of 12 plots.
• Plots varied in size from 0.040 ha. for the control, to 0.405 ha for the widest thinning.
• All trees in each plot are permanently tagged.

History:

• 1900 - stand naturally regenerates to lodgepole pine.
• 1952 - stand thinned by axemen when experiment established.
• 1958 onward - stand measured for growth-and-yield at 5-year intervals.
• 1980-83 - mountain pine beetle attack and mortality
• 1993 - 40-year assessment.
• 1998 - 45-year assessment.
• 1999 classified biogeoclimatically.
• 2000 unpublished progress report.

Status: Active

Reports and Publications:

Progress reports are associated with each assessment date.

Johnstone, W.D., 2002. Thinning lodgepole pine in southeastern British Columbia: 46-year results. Res. Br., B.C. Min. For., Victoria, B.C. Work. Pap. 63.

Comments:

This study is typical of many older growth-and-yield installations. There are few 50-year-old experiments, but this one is replicated only twice, and has suffered from mountain pine beetle mortality. Its continuation is under review.