Peatland black spruce

Introduction

Peatland forests, usually dominated by black spruce, account for roughly 25% of the productive forest land in the central portion of the Boreal Shield Ecozone. These forests often have considerable potential for natural regeneration, and forest harvesting practices have been evolving to take increasing advantage of this potential. Past research at the Great Lakes Forestry Centre on the ecology of peatland forests and on assessing and developing harvesting practices has made a substantial contribution to this evolution. Research on alternative silvicultural systems is continuing in the Lake Abitibi Model Forest.

Many peatland forests can be harvested at a range of intensities, varying from clearcut to light partial cuts. The effects of harvest intensity on subsequent stand development are not well understood. There is some evidence that rotations can be considerably shortened by retention of residuals, but this possibility needs more rigorous examination.

Peat soils have low bearing strength and are susceptible to considerable disturbance when subjected to harvesting equipment traffic during the frost-free season. Little is known about the physical and biological consequences of site disturbance on peatlands.

Objectives

The objectives of this study are:

1. To examine the effects of partial harvest techniques on stand structure, development and growth of peatland black spruce forests. This is being done through continued measurement of existing silvicultural experiments and through the development of models to forecast stand growth and development.
2. To examine the physical and biological consequences of site disturbance on peatland. This is being done through long-term observations of peatland site disturbance experiments. 

Selected publications

Groot, A. 1984. Stand and site conditions associated with abundance of black spruce advance growth in the Northern Clay Section of Ontario. Dept. Env., Can. For. Serv., Info. Rept. O-X-358.

Groot, A. 1987. Silvicultural consequences of forest harvesting on peatlands: site damage and slash conditions. Gov't of Canada, Can. For. Serv., Info. Rept. O-X-384.

Groot, A.; Horton, B.J. 1994. Age and size structure of natural and second growth peatland Picea mariana stands. Can. J. For. Res. 24: 225-233.

Groot, A. 1996. Regeneration and surface condition trends following forest harvesting on peatlands. NODA Tech. Rep. TR-26. 12 p. + append.

MacDonell, M.R.; Groot, A. 1996. Unevenaged silviculture for peatland second-growth black spruce: biological feasibility. NODA Tech. Rep. TR-36.

MacDonell, M.R.; Groot, A. 1997. Harvesting peatland black spruce: Impacts on advance growth and site disturbance. For. Chron. 73: 249-255.

Groot, A. 1998. Physical effects of site disturbance on peatlands. Can. J. Soil Sci. 78: 45-50.

Hökkä, H.; Groot, A. 1999. An individual-tree basal area growth model for second-growth peatland black spruce. Can. J. for. Res. 29: 621-629.

Groot, A.; Hökkä, H. 2000. Persistence of suppression effects on black spruce advance regeneration after overstory removal. Can. J. For. Res. 30: 753-760.