A DENDROECOLOGICAL ANALYSIS OF EASTERN LARCH (LARIX-LARICINA) IN SUB-ARCTIC QUEBEC

Two new dendrochronological series of eastern larch extend from 1710-1987 (Whapmagoostui-Kuujjuarapik, E Hudson Bay) and from 1596-1978 (Riviere aux Feuilles, W Ungava). Generally, conditions were more favorable for growth at the end of the 19th century and during the 20th century than before. A comparison of several larch and white spruce Picea glauca tree-ring series from N Quebec indicates significant shared variance between regions and species. Larch chronologies show two important depressions during the 20th century, between 1905-1908 and 1940-1946, which are more obvious in the 2 series from the southern forest-tundra. These may be caused by outbreaks of larch sawfly Pristiphora erichsonii. -from Authors