Canadian Forest Service Publications
Résistance comparée de l'épinette blanche et du sapin baumier au renversement. 2002. Meunier, S.; Ruel, J.C.; Laflamme, G.; Achim, A. Can. J. For. Res. 32 : 642-652.
Issued by: Laurentian Forestry Centre
Catalog ID: 22734
Availability: PDF (request by e-mail)
Information on eastern Canadian tree species vulnerability to windthrow is scarce. Some statements on relative species vulnerability have been made but they rely on empirical observations, which are often difficult to generalize. In this context, a study was conducted to compare the overturning resistance of balsam fir (Abies balsamea (L.) Mill.) and white spruce (Picea glauca (Moench) Voss) on a mesic site. To establish which tree characteristics would best explain the critical turning moment, simple linear regressions were calculated using tree dendrometric data. The best regressions were obtained with stem weight. With this variable, resistance to overturning did not differ between the two species. Only regressions involving total height showed a significantly greater resistance for white spruce. This difference can be explained by a difference between the species in height–diameter relationships. For a similar height, spruce has a greater diameter, involving a higher stem weight and thus a greater resistance. Decay did not play a major role in our experiment as trees with external defects were excluded. Our results suggest that to minimize losses from windthrow, silvicultural treatments on mesic sites should try to increase the proportion of trees of either species with the lowest height/diameter ratio.