The Alaska Vegetation Classification - Alaska Geobotany Center ...

Closely related types-These communities are closely related to the mixed herband fern types but have more cover of Heracleum lanafum or Angelica spp. Communitiescontaining Elymus arenarius are closely related to some of the elymus (drygraminoid herbaceous) types but have more umbels and less elymus.Primary reference-Byrd 1984.CommunitieoHeracleum lanatum-Veratrum viride-Senecio triangularis (Cooper1942, Fox 1983). Heracleum lanatum-Athyrium filix-femina-Angelica lucida (Byrd1984, Friedman 1982). Artemisia tilesii-Heracleum lanafum-Elymus arenarius (Byrd1 984).111.8.2.6. FernsDescription-These communities are Characterized by a lush growth of ferns, oftenAthyrium filix-femina or Dryopferis spp. Herbs, grasses, and sedges may be commonbut are inconspicuous. Woody plants are absent or rare, mosses may be common,and lichens may be present. Cover is complete or nearly so.Distribution and site characteristics-Fern communities usually are found at lowelevation in localized patches in relatively deep, well-drained, moist soils in southeasternand south-central Alaska and the Aleutian Islands. These sites are snowcovered in winter but become snow free early in spring. Permafrost is absent. Thesingle community reported is at the bases of rock cliffs at low elevations in theAleutian Islands.Successional status-Successional relations are unknown.Closely related types-Fern communities can be similar to large umbel communitiesand mesic mixed herb communities but are strongly dominated by ferns.Primary referenceqank 1951Communities-Athyrium filix-femina-Cystopteris fragilis-Botrychium spp.-Gymnocar~iumdryopferis (Bank 1951)111.8.3. Wet Forb HerbaceousThese wet forb communities occur on soils saturated with water or semipermanentlyflooded.lll.B.3.a. Fresh Herb MarshDescription-Fresh herb marsh communities are dominated by emergent herbs indeep water (15 centimeters [6 in] or more). Characteristically, the dominant or codominantemergent is Equisetum fluviatile; although it is not really an herb, it isincluded with true herbs on the basis of being nongraminoid and nonwoody. Commonassociated emergent herbs (sometimes codominant) include Menyanthes frifoliataand Potentilla palustris. Floating-leaved or submerged aquatic plants, such asPotamogeton spp., Hippuris vulgaris, and Myriophyllum spicatum. may be presentor even abundant. Aquatic mosses often are common. Woody plants and lichensare absent. Plant cover is open.195