They passed alder swamps and bamboo groves and pale green reindeer moss.
An erect, grayish, branching lichen (Cladonia rangiferina) of Arctic regions, constituting the chief source of food for reindeer and several other herbivores
an erect grayish branching lichen of Arctic and even some north temperate regions constituting the chief food for reindeer and caribou and sometimes being eaten by humans