Objectives:

• To assess the logistical feasibility of using stump removal as a post-harvest treatment in small patch cuts in the ICHmw3, and to provide a demonstration area for the use of this treatment.
• To compare the survival and growth of artificial regeneration of Douglas-fir, western larch, and paper birch in a small patch clearcut silvicultural system, and
• To assess the effectiveness of stump removal as a method of reducing impacts of Armillaria root disease by comparing the survival and growth of the seedlings in the stumped with that in the un-stumped treatments.

Experimental Design:

Treatments:

The 13.3 ha area was stratified into 4 site series/treatment units. Two of the treatment units - the dry flat and the dry sloped were split with one half conventionally logged and the other half push-over logged. In each of the treatments, three species were planted in alternate rows: western larch, Paper birch, and interior Douglas-fir. Rates of growth of the three species will be followed for 10 years. 10 years is the minimum amount of time for Armillaria root disease to express itself and result in potential differences to seedling survival and growth.

History:

• 1992 - Plot layout and initial assessment
• 1993 - Harvest
• 1994 - Planting
• 1995-1997 Assessments and progress report
• 1999 Remeasurement and final report.

Status: Dormant

Reports and Publications:

Ketcheson, M.V., 1992. Wetask Lake Silvicultural Systems Demonstration Forest Establishment Report, B.C. Min. For., Nelson, B.C.

Bauer, P., and C. Thompson, 2000. Wetask Lake Silvicultural Systems Trial: A Seedling Trial comparing Patch Clearcut Silvicultural Systems using Conventional Harvesting Methods and Post-harvest Stumping for Armillaria Root Disease Infected stands. Final Report submitted to Science Council of BC for Project FR-96/97-482.

Comments:

After five years, stumping had no effect on height or diameter growth of the three species planted. There was more Armillaria-caused Douglas-fir mortality in the unstumped treatment (9 trees) compared to the stumped treatment (1 tree). Armillaria-caused larch mortality (38 trees) was much greater than Douglas-fir mortality (10 trees), but the larch mortality was equally divided between the stumped (18 trees) and unstumped (20 trees) treatments. Larch foliage disease was common, and this likely predisposed the trees to root disease, regardless of stumping treatments.