Unga Island, the largest of the Shumagin Island Group, is situated on the Pacific side of the Alaska Peninsula. It is 100km away from the Aleutian trench and is considered to be part of the Aleutian volcanic forearc. There are no active volcanoes on the island, however the topography illustrates its past volcanic history. Due to its volcanic origin and past glaciations, the vegetation is predominately treeless tundra. Consequently, the flora of the island is predominately composed of lichens, mosses, grasses, sedges, flowering plants and thickets of shrubs. The climate of the arc region is another major factor supporting this tundra ecotype. During the winter snow covers the entire region, however by May the snow completely melts. Summer brings frequent rain (annual rainfall of 45 to50 inches), fog, and windstorms.