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Subalpine Tall Herb Vegetation, Site and Standing CropBy HILMAR HOLMENIn Swedish vegetation not many spontaneous plantcommunities show such a luxuriance as some of themeadow forests with a tree layer of spruce andbirch in the pre-alpine and subalpine regions. Thisluxuriance appears so striking through the strongcontrast between the meadow forest and adjacentwoods of heath type. In the area of woodland andlow mountains N and W of Lake Ankarvattnet inFrostviken, the northernmost parish of the provinceof Jamtland, these two types of vegetationare weU developed.Two thirds of the land area of Frostviken isoccupied by treeless low mountains (the highestpeak is 1314 m; 4310 ft.), the rest being woodland,predominantly spruce forests, but also the usualsubalpine belt of chiefly birch. Beside spruce andbirch occur also pine, rowan, grey alder, aspen andbird-cherry (Prunus padus). However, none of thelatter species form stands, not even pine, here arare species, but occur interspersed in the spruceand birch forests. As there have been only fewand restricted forest fires in this area, spruce hasgained the upper hand over pine (FESTIN 1922,ARNBORG 1952).The bedrock within the area studied consistsmainly of weakly metamorphic schists ("koli sediments"),in which clayey, marly, limy and quartziticlayers or layer series are included (MAGNUS­SON et al. 1963). In the schists there are sometimesfairly broad veins of pure quartz.In the Bjuralven valley, 7 to 8 km N of LakeAnkarvattnet, there is a long narrow course ofmarble extending far into Norway in its westernpart (ANGEBY 1947). The most typical karst areain Scandinavia is situated here (SvENONIUS 1880,FEsTIN 1922, ANGEBY 1947, SoRLIN 1948).This river valley was the home of the last nativepopulation of beaver in Sweden. The last beaverwas shot in 1871 (FESTIN 1922, p. 58), two yearsbefore (!) the beaver became protected by law.Glacial till is the only mineral substrate. Fartherto the SW, near Lakes BHi.sjon and Jormvattnet,there are sediments from ice-dammed lakes (A.NGE­BY 1947).In the forested land as well as above the tree linepeat areas are common, being usually divided intosmaller parts. A few borings and sections on a roadshow maximum depths of 2.5 m.Precipitation as well as temperature varystrongly with altitude in this rugged area. It seemslikely that the annual precipitation on an averagemay be about 1000 mm (40 inches) and the meanannual temperature about -I 00 for the particulararea studied (see ANGSTROM 1958), which extendsbetween Lake Ankarvattnet, at 448 m, and Mt.Mesklumpen, a low-alpine phyllite mountain, at925 m.Some general features of the vegetationTHE LOW-ALPINE REGION has a vertical extent ofabout 150 m. The larger part of the wind-exposedtop-plateau of Mt. Mesklumpen is occupied by anEmpetrum hermaphroditum heath poor in species,with Carex Bigelowii and Rubus chamaemorus inmoist depressions. As is often the case, no indicatorsof lime occur on the leached plateau. On thesouth-facing slopes influenced by oozing waterthere are, however, many species indicative of alime-rich site. Thus Dryas octopetala is common onsuch localities and in places sheltered from N andW winds the community is rich in species. Thefollowing species list is from a south-exposed slope.Acta Phytogeogr. Suec. 50