Montana Field Guide

Reindeer lichen (an association of a fungus and an alga) is a fruticose lichen forming grey-green thick cushions on the ground in boreal and sub-arctic-tundra regions. (Fruticose lichens are radially symmetrical, the thallus being more or less round.) Branches arising from the thallus have tips that are swept in more or less the same direction. Growth occurs by producing new branches each year, as well as by elongation of older branches.