Commercial Thinning Workplan - 130-208

Description: Commercial thinning involves the partial harvest of merchantable trees from forest stands, so that wood fibre is immediately obtained for processing. In theory, the trees left behind will potentially grow faster, directing the growth potential of the site to selected trees that are free of competition. The net effect is to reduce the amount of time it takes these trees to reach merchantable size. There is evidence that this practice also minimizes the potential damage that can be inflicted on a forest stand, by wildfire. Although commercial thinning has existed as a forest management practice for some time, and has been used extensively in several provinces including British Columbia, Alberta, and New Brunswick, only a few trials have been undertaken in Ontario, with somewhat inconsistent monitoring and measurement.

Interest in commercial thinning of jack pine, white spruce and black spruce stands within the boreal forest has been increasing for some time. However, commercial thinning is rated as "not recommended" in the Silvicultural Guide (1997). This rating is based primarily upon not satisfying criteria, and unfortunately, a literature review, knowledge synthesis or problem analysis of commercial thinning in the boreal forest does not exist in the literature of the public domain. A literature review organized with a knowledge synthesis framework and accessible within the public domain is necessary in order to move the decision-making and debate onto a common factual basis.

The desired outcome of this project is the approval of commercial thinning as a cost effective; silviculturally appropriate tool for use in forest management and the elimination of impediments to large-scale implementation (>3000ha/yr) of commercial thinning in Boreal Northeastern Ontario. This project focuses on three main issues: cost and operations, allocation, and policy.
The specific objectives for this project are:

  • To initiate a program of commercial thinning research and exceptions monitoring to ultimately determine the effectiveness of this treatment in meeting the objectives of management of white spruce, black spruce and jack pine;
  • To begin a process of having input into silvicultural guides and the associated treatment rating system. The addition of a 'developmental' category and the recognition that commercial thinning is 'ecologically appropriate' is an important first step; and
  • The implementation of a knowledge synthesis and problem analysis in a FRP/MNR partnership to ensure that when discussion on policy issues begin, all parties will have the same level of knowledge and understand the issues.

The ultimate goal of this project is to change the commercial thinning guidelines in the boreal forest from ‘not recommended’ to ‘recommended with conditions’. These conditions are currently under review, and the synthesis should help to influence the guidelines.


The Project Team:  Gordon Kayahara, OMNR, Jeff Leach, Tembec, Leanne McKinnon, OMNR, Vic Wearn, Algo-Temp Forest Services




Impact of commercial thinning on annual diameter growth and wood density in black spruce plantations grown in Kapskasing, Ontario


Technical Notest/ Reports:

McKinnon, L.M., G.J. Kayahara and R.G. White. 2006. Biological framework for commercial thinning even-aged single-species stands of jack pine, white spruce, and black spruce in Ontario. Ontario Ministry of Natural Resources, Science and Information Branch, Northeast Science and Information Section, South Porcupine, ON. Technical Report TR-046. 126 pp.

Kayahara, G.J., L.M. McKinnon and R.G. White. 2006. Commercial Thinning Specifications and Exceptions Monitoring Protocol for Jack Pine, White Spruce and Black Spruce in Ontario’s Boreal Forest. OMNR, Northeast Science & Information, NESI Technical Note TN-022. 8 pp.

[Draft] McKinnon, L.M., G.J. Kayahara, White R.G. and M.E. Woods. Implementing Commerical Thinning in Boreal Ontario- A Problem Analysis with Recommendations. DRAFT Technical Report TR-047. 55 pp.


Tree Tips:

Tree Tip for Project 130-208


Status Reports:

Status Report (2007-2008)

Project Work Report (2007-2008)


For Additional Information Contact:

This e-mail address is being protected from spambots. You need JavaScript enabled to view it