Alaska Arctic Vegetation Unit P2.1

Barren Complexes: B2.1B2.1 Lichens on Lava (Seward Peninsula) - B3d.1B3d.1 Acidic mountain complexes (St. Lawrence Is.) - B3e.1B3e.1 Acidic mountain complexes (Brooks Range) - B3e.2B3e.2 Acidic mountain complexes (NW Alaska) - B3e.3B3e.3 Acidic mountain complexes (Kuskokwim Mtns.) - B4d.1B4d.1 Nonacidic mountain complexes (Seward Peninsula) - B4d.2B4d.2 Nonacidic mountain complexes (St. Lawrence Is.) - B4e.1B4e.1 Nonacidic mountain complexes (Brooks Range) - B4e.2B4e.2 Nonacidic mountain complexes (NW Alaska) || Non-Tussock Graminoid Tundras: G3.1G3.1 Moist nonacidic tundra (N. Arctic Coastal Plain) - G3.2G3.2 Moist nonacidic tundra (St. Lawrence Is.) - G3.3G3.3 Moist nonacidic tundra (Arctic Foothills, Seward Peninsula) || Tussock Graminoid Tundras: G4.1G4.1 Tussock tundra (entire map) - G4.2G4.2 Lichen-rich tussock tundra (Seward Peninsula) - G4.3G4.3 Tussock tundra on sands (Arctic Coastal Plain) || Prostrate Dwarf-Shrub Tundras: P2.1P2.1 Dry tundra (St. Matthew Is.) || Erect Dwarf-Shrub Tundras: S1.1S1.1 Shrubby, tussock tundra (NE Alaska) - S1.2S1.2 Dwarf-shrub, lichen tundra (NW Alaska) - S1.3S1.3 Dwarf-shrub tundra on volcanic rock (Yukon-Kuskokwim Delta) - S1.4S1.4 Dwarf-shrub, lichen tundra (Kuskokwim Mtns.) || Low-Shrub Tundras: S2.1S2.1 Willow-birch tundra (entire map) - S2.2S2.2 Alder shrublands (entire map) || Wetlands: W1.1W1.1 Wet acidic coastal complex (N Alaska) - W1.2W1.2 Wet nonacidic coastal complex (N Alaska) - W2.1W2.1 Wet acidic complex (N Alaska, Seward Peninsula) - W2.2W2.2 Wet nonacidic complex (Subzone D, N Alaska) - W3.1W3.1 Wet acidic complex with tussock tundra (W Alaska) - W3.2W3.2 Wet acidic complex with dwarf-shrub tundra (lower parts of Yukon-Kuskokwim Delta) - W3.3W3.3 Wet acidic complex with low-shrub tundra (Yukon-Kuskokwim Delta) - W3.4W3.4 Wet acidic complex with dwarf-shrub tundra (inland parts of Yukon-Kuskokwim Delta) - W3.5W3.5 Wet acidic complex (Nunivak Is.) - W3.6W3.6 Wet nonacidic complex (warmer parts of NW Alaska) - W3.7W3.7 Wet coastal saline tundra (Yukon-Kuskokwim Delta)

Hierarchy of Geobotanical Vegetation Map Units (Walker DA 2002)

Lush lichen growth on Hall Island, St. Matthews group. Dry tundra. 1985. Photo: D.R. Klein.

$The thick mats of fruticose lichens that dominated much of the landscape in the southern portion of St. Matthew Island prior to the introduction of reindeer had been greatly depleted by reindeer grazing when vegetation plots were established there (Station # 2) in early August 1957. Only fragments of fractured lichens and moss remained on the ground surface in the depressions between the dark green willow hummocks.Photo: 1957. D.R. Klein.$

This lichen-dominated plant community with scattered hummocks of willow is on Hall Island that was never reached by the reindeer. It serves as a control for assessing the grazing impact of reindeer on similar communities on St. Matthew Island. Photo: D.R. Klein.

P2.1 Dry tundra (St Matthew Island)