Title
Icelandic birch scrub (Betula pubescens subsp. czerepanovii) with dwarf shrubs (Vaccinium uliginosum, Empetrum nigrum, Arctostaphylos uva-ursi, Calluna vulgaris, Betula nana, Salix lanata), locally with herbs and grasses (Geranium sylvaticum, Rubus saxatilis, Equisetum pratense, Deschampsia flexuosa, Luzula multiflora)
Geographical distribution
Country/territory
Iceland: present on the whole area of the country; for instance in the Fjord areas of east, north and north-west Iceland and in lower situated parts of the central highlands with stronger winterly snow covering
area frequency
108 polygons.
Scientific names of main plant communities and their most common synonyms (with author citation)
Betulo-Arctostaphyletum Glawion 1985; Vaccinium uliginosum-Empetrum soc. Steindórsson 1974; Empetrum-Deschampsia flexuosa soc. Steindórsson 1974; Vaccinium uliginosum-Empetrum-Calluna vulgaris soc. Steindórsson 1974; Empetrum-Arctostaphylos uva-ursi soc. Steindórsson 1974 (= Empetro-Betuletum pubescentis Nordhagen 1943°).
Structural feature of the main community(ies) (layers, life-forms, etc.)
The vegetation forms the potential upper forest belt and consists of shrub vegetation of up to 2 m high birches (Betula pubescens subsp. czerepanovii), scattered with Sorbus aucuparia and shrub layer species that are mainly contiguous where they are present, and occasionally open; mostly with low dwarf shrubs, sometimes also with herbs that sometimes outgrow the dwarf shrubs.
Dominant and most frequent species in different layers
Tree layer
Betula pubescens subsp. czerepanovii, occasionally Sorbus aucuparia
Shrub layer
Salix lanata, Juniperus communis subsp. alpina, Betula nana
Herb layer
Vaccinium uliginosum, Empetrum nigrum, Arctostaphylos uva-ursi, Calluna vulgaris, Geranium sylvaticum, Rubus saxatilis, Ranunculus acris, Equisetum pratense, Agrostis vinealis, Agrostis capillaris, Deschampsia flexuosa, Festuca rubra, Hierochloe odorata, Luzula multiflora, Carex vaginata
Moss layer (incl. lichens)
Hylocomium splendens, Rhytidiadelphus squarrosus, Rhytidiadelphus triquetrus, Sanionia uncinata, Peltigera canina
Diagnostically important species
Betula pubescens subsp. Czerepanovii; Arctostaphylos uva-ursi, Geranium sylvaticum, Rubus saxatilis, Luzula multiflora, Empetrum nigrum, Thymus praecox subsp. arcticus, Alchemilla alpina
Ecological variants
According to Glawion1985: Subassociation of Betula nana with chionophilous species.
Geographical variants (geogr. differential species)
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Natural accompanying vegetation (most important units in complex with the name giving mapping unit, scientific names)
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Adjoining climax and permanent vegetation (with numbers of mapping units)
south arctic tundras (B6), arctic scrub tundras (B16), mountain tundras and vegetation (B34, B35), birch forests (C7), dune vegetation (P1), transition bogs (S17), small sedge-brown mires (S22).
Land use, substitute communities
forestry (substitute communities, plantations of economic tree-species, scrub)
Some civic regions have carried out afforestation in order to create a leisure and recreational landscape. In addition, a number of experimental silvicultural areas are distributed over the landscape. Recently, large areas have been afforested for soil protection purposes. For soil protection, the native birch (Betula pubescens) is the most important tree species, as it is for creating the leisure and recreation landscapes. Alnus sinuata, Salix alaxensis, Picea sitchensis, Pinus contorta and Larix sibirica are other important species.
grassland (meadows, pastures, herb-rich communities)
Pasture land, mainly with grass dwarf shrub vegetation.
arable land (characteristic weed communities)
Cultivated areas for hay production; Poa annua, Alopecurus geniculatus, Stellaria media and Taraxacum spp. are the most widespread weed species.
settlements (typical ruderal vegetation)
In this area there are a number of farmhouses and hamlets. The most important components of the ruderal vegetation are Stellaria media, Capsella bursa-pastoris, Senecio vulgaris, Polygonum aviculare, Ranunculus repens, Elymus repens, Poa annua, Rumex longifolius, Matricaria discoidea, Spergula arvensis and locally Cirsium arvense.
Site conditions of the mapping unit
Landscape type, geomorphology
Valley slopes and mountains, more severely exposed and/or at greater heights than the birch forests (C7); occasionally at climatically favourable locations within the unit B16, such as at the tips of the outer fjords and bays and at lower-lying valleys of the mainland interior.
Altitudinal belt and/or altitudinal range
0-400 m, at the edges of the central highlands up to 550 m
Geology (bedrock)
glacial, marine and fluvioglacial sediments (Holocene); alkali rocks (Quaternary, Tertiary)
soil type, also the depth of fine textured earth (soil), stone content; (international nomenclature)
andosols; (orthic podzols; vitric andosols)
soil moisture, water balance
fresh, moderately dry
soil reaction
weakly acidic
soil fertility
meso-eutrophic
Climate incl. local climate
climate type (following Walter & Lieth)
IX (VIII)
average annual temperature
2-4,5 °C
average annual precipitation
400-2200 mm
average temperature of the warmest month
8,5-11,5 °C
average temperature of the coldest month
-3 to 1 °C
local climate or other climatic peculiarities
arctic boreal - cold temperate.
Importance for nature protection
Present state and development trend of natural vegetation (degree of endangerment)
Currently only 100,000 of formerly 814,000 ha (approximately 8.4 % of the total area of Iceland) of this vegetation type remains. The greater part of the area is used during summer for sheep grazing, although the pressure from grazing is receding. With the exception of a few sites, the stands are not directly threatened by grazing. Wide areas have been reshaped particularly near population centres for leisure and recreational purposes. A potential threat to the shrub communities in these areas arises from the cultivation of introduced species. Since many of these areas are very small and sensitive to human activities, they should be protected.
endangered communities, species worthy of protection in natural vegetation
There are smaller areas with naturally occuring Populus tremula, which are not endangered at the moment, but should nevertheless be protected. Besides in some smaller areas of the vegetation type, mostly in south-east Iceland, some very rare species of epiphyte lichen can be found (see C7).
causes of endangerment
Local overgrazing and urban development with plantation of introduced species.
required measures for protection and restitution
The greater part of the birch shrub forests, whether owned privately or by the government, is protected by forestry legislation that prohibits the clearing and clear-felling of birch forests and scrub stands and the winter grazing of livestock. Control measures are necessary to ensure that birch scrub is not converted into plantations with non-indigenous woody plants. Protection of representative areas from increased leisure and recreational use.
Localities of representative stands (loci typici) with state of protection
of the natural vegetation
Iceland: Baejarstadarskógur in the Skaftafell national park, the state forests Vaglir, Thórdarstadur and Hallormsstadur.
of characteristic substitute communities worthy of protection
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Most important references (author, year)
Glawion 1985; Steindórsson 1974
Compiled by
E. Einarsson, G. Gudjónsson, Th.H. Jónsson
