SPATIOTEMPORAL DISTRIBUTION OF LIGHT RINGS IN SUB-ARCTIC BLACK SPRUCE, QUEBEC

Numerous subfossil trees from the 13th, 14th, and 15th centuries sampled in the Riviere Boniface area (east of Hudson Bay) made it possible to extend to A.D. 1221 a previously published light-ring chronology. The spatial distribution of these diagnostic rings was studied along a south-north and a west-east transect in several sites extending from the northern limit of the Boreal Forest Region to the tree line. Data showed an increase in the number and frequency of light-ring years among populations along the south-north transect but little variations along the west-east transect.