GROWTH RATES OF CLADONIA ALPESTRIS, C. MITIS, AND C. RANGIFERINA IN THE TALTSON RIVER REGION, N.W.T.

Abstract

Data on the growth rate of lichens are essential to the understanding of the carrying capacities of rangelands used by caribou and reindeer in Canada. Recent Russian literature suggests fruticose lichens have three growth stages. The first stage is one of podetium accumulation. During the second stage, accumulation rate and decomposition rate are similar, while, in the third stage, decomposition of the Podetium is more rapid than accumulation. In the Taltson River region, the average annual linear growth rates of Cladonia alpestris, Cladonia mitis, and Cladonia rangiferina as determined by dividing the number of joints on the living podetium by the height of the living portion of the podetium, are 3.4, 3.6, and 4.1 mm, respectively. These rates are less than those reported from Russia, Newfoundland, and northern Saskatchewan.