Title
Icelandic birch forests (Betula pubescens, Betula pubescens subsp. czerepanovii), with herbs and grasses (Geranium sylvaticum, Rubus saxatilis, Galium boreal, Equisetum pratense, Deschampsia flexuosa), locally with dwarf shrubs (Vaccinium uliginosum, Vaccinium myrtillus, Empetrum nigrum, Arctostaphylos uva-ursi) partly hygrophilous with Angelica sylvestris, Geum rivale, Filipendula ulmaria
Geographical distribution
Country/territory
Iceland: in all parts of the country except for north-west Iceland and the central high plain
area frequency
32 polygons.
Scientific names of main plant communities and their most common synonyms (with author citation)
Geranio-Betuletum (Nordhagen 1928) 1943 korr. Dierßen 1982, (Rubo saxatili-Betuletum pubescentis Glawion 1985; Rubus saxatilis-Geranium sylvaticum soc. Steindórsson 1974, Rubus saxatilis-Deschampsia flexuosa soc. Steindórsson 1974, Hierochloe odorata-Agrostis tenuis-Equisetum pratense soc. Steindórsson 1974).
Structural feature of the main community(ies) (layers, life-forms, etc.)
2-12 m high stands of Betula pubescens subsp. pubescens and subsp. czerepanovii, sporadically with Sorbus aucuparia (4-8 m) and Populus tremula (1-6 m), frequently with a shrub layer of Salix phylicifolia (1-4 m) and Salix lanata (m >1,5); contiguous herb layer, and a moss layer is always present.
Dominant and most frequent species in different layers
Tree layer
Betula pubescens subsp. pubescens, Betula pubescens subsp. czerepanovii, scattered Sorbus aucuparia, isolated Populus tremula-stands
Shrub layer
Salix phylicifolia, Salix lanata, Juniperus communis subsp. alpina
Herb layer
Geranium sylvaticum, Rubus saxatilis, Ranunculus acris, Galium boreal, Galium normanii, Galium verum, Equisetum pratense, Agrostis capillaris, Hierochloe odorata, Anthoxanthum odoratum, Poa nemoralis, Festuca rubra, Carex vaginata, Deschampsia flexuosa, Vaccinium uliginosum, Vaccinium myrtillus, Empetrum nigrum, Arctostaphylos uva-ursi
Moss layer (incl. lichens)
Hylocomium splendens, Rhytidiadelphus squarrosus, Rhytidiadelphus triquetrus, Sanionia uncinata, Peltigera canina
Diagnostically important species
Betula pubescens subsp. pubescens, Betula pubescens subsp. czerepanovii; Salix phylicifolia; Geranium sylvaticum, Rubus saxatilis, Ranunculus acris, Hierochloe odorata, Trifolium repens
Ecological variants
According to Glawion 1985: variants of seeping wet eutrophied sites with Alchemilla vulgaris, Angelica sylvestris; subassociation on nutrient impoverished soils and a raw humus horizon with Vaccinium uliginosum; variant of xeromorphic species on dehydration-sensitive, shallow habitats, chamaephyte-rich variant with Vaccinium myrtillus where a lasting winter snow coverage is present.
Geographical variants (geogr. differential species)
In the area around Egilsstadir in the central part of eastern Iceland to Skaftafell in south-east Iceland, epiphytic lichens are considerably more frequent on the birch stems than they are in other parts of the country. Only in eastern Iceland is Campanula rotundifolia a characteristic species of the herb layer.
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 scrub forests (C8), dune vegetation (P1), transition bogs (S17).
Land use, substitute communities
forestry (substitute communities, plantations of economic tree-species, scrub)
The annual afforestation rate is 1000-2000 ha and increasing. Native birches (Betula pubescens) contribute 20-25 % towards the newly planted stands. The most important commercial plantation species are Larix sibirica, Picea sitchensis and Pinus contorta, while Populus trichocarpa is also present, although this is currently of lesser economic importance.
grassland (meadows, pastures, herb-rich communities)
Pasture land with grass-dwarf shrub vegetation (Leontodon-Trifolium repens pastures, Calluno-Vaccinietum); land for hay and straw making.
arable land (characteristic weed communities)
The most widespread weed species include: Poa annua, Alopecurus geniculatus, Stellaria media and Taraxacum spp.
settlements (typical ruderal vegetation)
In this area there are many agricultural holdings and a number of villages. The main components of the ruderal vegetation include: Stellaria media, Capsella bursa-pastoris, Senecio vulgaris, Ranunculus repens, Poa annua, Elymus repens, Taraxacum spp., Matricaria discoidea, Rumex longifolius, Spergula arvensis, Stellaria graminea and locally also Anthriscus sylvestris and Cirsium arvense.
Site conditions of the mapping unit
Landscape type, geomorphology
in valleys (valley bases), at slopes of protected valleys and at lower altitudes of southern and western exposed mountain slopes with relatively high temperatures
Altitudinal belt and/or altitudinal range
0-250 m
Geology (bedrock)
marine and glacial sediments (Holocene); alkali rocks (Tertiary)
soil type, also the depth of fine textured earth (soil), stone content; (international nomenclature)
andosols; (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
2,5-5 °C
average annual precipitation
500-1800 mm
average temperature of the warmest month
10-12 °C
average temperature of the coldest month
-3 to 0 °C
local climate or other climatic peculiarities
Birch forests occur in the thermic favoured regions of the south and southwestern parts of the country, but only at places protected by wind, because the usual southwestern wind is strongly saliferous.
Importance for nature protection
Present state and development trend of natural vegetation (degree of endangerment)
Today only 2,400 of originally 440,000 ha (4.5 % of the total area of Iceland) of these forests remain. Major parts of the birch forests are protected in national parks, state forests and some private forests. They are fenced off and are being managed conservatively, although conifers have been added occasionally for timber production.
endangered communities, species worthy of protection in natural vegetation
There are small areas with naturally occuring Populus tremula-stands, which are not yet endangered at the moment, but in any case worthy of protection. Besides there are smaller parts of the birch forest, mostly in south-east Iceland, the only site of some very rare epiphyte lichen in Iceland, like for instance Bryoria simplicior, Bryoria fuscescens, Evernia prunastri, Hypogymnia farinacea, Nephroma bellum, Parmeliopsis hyperopta, Pseudovernia furfuracea, Melanelia septentrionalis, Caloplaca borealis, Platismatia glauca and Usnea subfloridana. Many of these areas are very small and susceptible to human activity and should therfore be protected.
causes of endangerment
The threat of transformation into plantations with non-indigenous woody plant species.
required measures for protection and restitution
All birch forests, whether governmental or private, are protected by forestry legislation that prohibits the clearing and clear-felling of birch forests and birch scrub and the winter grazing of livestock. Control measures are necessary to ensure that the birch forests are not converted into plantations with non-indigenous woody plants.
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)
Dierssen 1996; Glawion 1985; Hövelmann 1995; Steindórsson 1974
Compiled by
E. Einarsson, G. Gudjónsson, Th.H. Jónsson
