| any of several lichens of the genus Cladonia, esp. the gray, many-branched C. rangiferina, of arctic and subarctic regions, eaten by reindeer and caribou. |

| reindeer moss n. An erect, grayish, branching lichen (Cladonia rangiferina) of Arctic regions, constituting the chief source of food for reindeer and several other herbivores. |
reindeer moss
(Cladonia rangiferina), a fruticose (bushy, branched) lichen found in great abundance in Arctic lands. It is an erect, many-branched plant that grows up to 8 cm high, covers immense areas, and serves as pasture for reindeer, moose, caribou, and musk oxen. In Scandinavia it has been used in the manufacture of alcohol, but difficulties in obtaining reindeer moss arise because of its slow growth rate (3 to 5 mm per year). Its periods of most rapid growth are spring and fall when high humidity and cool temperatures prevail.
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