Selection-cutting is the preferred method of logging in northern hardwood forests, because it is thought to favor the regeneration of valuable, shade-tolerant trees, maximize long-term productivity, and increase the health, quality and economic value of residual trees. Claims have also been made for the ecological sustainability of selection cutting, in particular that it: (a) preserves soil fertility; (b) maintains natural canopy composition; (c) protects plant and animal habitat. I evaluated these claims by studying the effects of selection-cutting on several measures of soil fertility (Ca, Al, Ca/Al molar ratios, pH), canopy composition and tree regeneration, herbaceous layer composition, and structural features related to habitat quality (cavity trees, snags, coarse woody debris) in 55 stands ranging from newly cut to old-growth (not all data overlaps). I found that forest growth after selection-cutting depletes soil solution calcium and lowers soil solution Ca/Al molar ratios, posing a threat to long-term forest health and productivity, particularly at higher elevations and in sites on siliceous bedrock. I found that selection-cut stands dominated by red oak (Quercus rubra) are converting to sugar maple (Acer saccharum) stands, posing a threat to both canopy and herbaceous layer diversity. I found no lasting effects of selection-cutting on herbaceous layer composition, diversity or quality, but I found indirect threats from the conversion of red oak stands to sugar maple and from depletion of soil solution calcium. Finally, I found that current selection-cutting practices generally do not meet published targets for large trees, cavity trees, snags and coarse woody debris, but that they probably could meet those targets with minor changes to cutting practices. I conclude by discussing the implications of these results for the management of northern hardwood forests.
| Identifer | oai:union.ndltd.org:uottawa.ca/oai:ruor.uottawa.ca:10393/28968 |
| Date | January 2003 |
| Creators | Stow, Nicholas |
| Contributors | Findlay, Scott, |
| Publisher | University of Ottawa (Canada) |
| Source Sets | Université d’Ottawa |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | 223 p. |
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