Pollen Analysis of Three Bogs on Vancouver Island, Canada

Abstract

Pollen analysis of three bogs along the southern half of the e. coast of Vancouver Island, Canada, reveals pollen profiles that reflect the progressively higher precipitation both present and in the past, northward along the east coast. There seem to be, however, no trends of postglacial forest succession that denote significant climatic fluctuations. The changes in forest composition probably represent normal forest succession. All three sections show a preponderance of Pinus contorta pollen in the lower levels, which in one it is predominant throughout. The precipitation differential in the three areas is best reflected by the profiles of Pseudotsuga taxifolia and Tsuga heterophylla. In the most northern section in the area of greatest precipitation, the latter is more abundant, while in the southern section in the driest region, the former is more abundant. In the area of intermediate rainfall, they are of about equal importance. The section in the driest region, near Victoria, also reflects the less mesic conditions by a record of Quercus garryana more consistent and abundant than in the other two.