Title
Baltic herb-rich open spruce forests (Picea abies) with Quercus robur and pine forests (Pinus sylvestris) with Brachypodium pinnatum, Hepatica nobilis, Asperula tinctoria, partly alternating with dry grasslands (Trifolium montanum, Filipendula vulgaris, Sesleria caerulea) and scrub (Juniperus communis, Corylus avellana, Cotoneaster integerrimus) on alvar limestone
Geographical distribution
Country/territory
Esthonia: north of the country and western islands
area frequency
14 polygons.
Scientific names of main plant communities and their most common synonyms (with author citation)
Arctostaphylo-Piceetum, Arctostaphylo-Pinetum, Arctostaphylo-Juniperetum, Calamagrostio-Piceetum, Calamagrostio-Pinetum, Calamagrostio-Coryletum, Seslerio-Pinetum (Laasimer 1965).
Structural feature of the main community(ies) (layers, life-forms, etc.)
Shallow limestone site with a thin soil or humus horizon. In nature, mixed spruce woods with Quercus robur and Fraxinus excelsior (a) normally prevail. The pine forests (b) probably arose secondarily due to forest grazing and fires. On extremely shallow rocky sites, natural scrub (c) and dry grasslands (d) occur. The tree layer is open and 15-20 m high (IV-V stand quality) while in the shrub layer Juniperus communis sets the tone, and less often Corylus avellana, with Ribes alpinum, Lonicera xylosteum, Cotoneaster integerrimus, Sorbus aucuparia, Daphne mezereum and Rhamnus cathartica also occurring. In the herb layer many species of xerophilic pine forests are represented (Arctostaphylos uva-ursi, Antennaria dioica, Thymus serpyllum) as well as dry grassland species (Filipendula vulgaris, Asperula tinctoria, Sedum album, Sedum acre, Trifolium montanum). Thermophilous fringe plants (Geranium sanguineum) and species of open xerophytic forests (Brachypodium pinnatum, Calamagrostis arundinacea, Galium boreal, Fragaria vesca, Sesleria caerulea, Carex flacca) are also frequent.
Dominant and most frequent species in different layers
Tree layer
a, b) Picea abies, Pinus sylvestris, Quercus robur, Fraxinus excelsior
Shrub layer
a-c) Juniperus communis, Corylus avellana, Ribes alpinum, Lonicera xylosteum, Cotoneaster integerrimus, Sorbus aucuparia, Daphne mezereum, Rhamnus cathartica, Frangula alnus, Berberis vulgaris, Potentilla fruticosa
Herb layer
a) Brachypodium pinnatum, Calamagrostis arundinacea, Rubus saxatilis, Fragaria vesca, Sesleria caerulea, Carex flacca, Galium boreal, Carex montana, Melica nutans, Hepatica nobilis;
b) Arctostaphylos uva-ursi, Antennaria dioica, Thymus serpyllum, Vaccinium vitis-idaea;
d) Filipendula vulgaris, Asperula tinctoria, Trifolium montanum, Galium verum, Geranium sanguineum, Cirsium acaule, Helictotrichon pratense, Festuca ovina, Sedum acre, Sedum album, Anthyllis vulneraria
Moss layer (incl. lichens)
Ditrichum flexicaule, Thuidium abietinum, Tortella tortuosa, Rhytidiadelphus triquetrus, Hylocomium splendens, Pleurozium schreberi, Cladina spp.
Diagnostically important species
Picea abies, Pinus sylvestris, Quercus robur; Potentilla fruticosa, Berberis vulgaris, Cotoneaster integerrimus; Brachypodium pinnatum, Hepatica nobilis, Asperula tinctoria, Geranium sanguineum, Filipendula vulgaris, Sesleria caerulea, Trifolium montanum
Ecological variants
see under the heading 'stand structure'
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)
Scrub communities (Juniperus communis, Corylus avellana), thermophilous fringe communities and dry calcareous grasslands.
Adjoining climax and permanent vegetation (with numbers of mapping units)
spruce forests (D19), pine forests (D47, D49), precious mixed broad-leaved forest (F70), salt vegetation (P21), raised bogs (S2, S9), brown mires (S20, S24), alder carr forests (T1).
Land use, substitute communities
forestry (substitute communities, plantations of economic tree-species, scrub)
open pine forests, scrub, thermophilous fringe communities.
grassland (meadows, pastures, herb-rich communities)
grazed secondary semi-dry grasslands.
arable land (characteristic weed communities)
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settlements (typical ruderal vegetation)
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Site conditions of the mapping unit
Landscape type, geomorphology
shallow sedimented limestone and dolomite (alvars)
Altitudinal belt and/or altitudinal range
lowland
Geology (bedrock)
limestone (Silurian, Ordovician), locally Pleistocene sediments (moraines, outwash, clays)
soil type, also the depth of fine textured earth (soil), stone content; (international nomenclature)
shallow humus carbonate soils (humus content: up to 20 %); (rendzic leptosols)
soil texture
loam and clay with rock fragments, rock
soil moisture, water balance
moderately dry to dry, locally periodically moist
soil reaction
neutral to weakly alkaline
soil fertility
mesotrophic
Climate incl. local climate
climate type (following Walter & Lieth)
VI(VIII), VII(VI)2, VIII(VII)1
average annual temperature
5-6 °C
average annual precipitation
500-600 mm
average temperature of the warmest month
16-20 °C
average temperature of the coldest month
-6 to -3 °C
local climate or other climatic peculiarities
Distinctively dry in summer.
Importance for nature protection
Present state and development trend of natural vegetation (degree of endangerment)
The current forests and scrub on alvars arose from spruce and oak forests as a result of clearing, fires and cattle grazing. spruce plays a greater role in the ungrazed stands. All forests of this mapping unit have been anthropogenically shaped for a long period of time; it is therefore exceptionally difficult to evaluate their natural state.
endangered communities, species worthy of protection in natural vegetation
No details
causes of endangerment
Forest clearing, fires, cattle grazing.
required measures for protection and restitution
Strict protection of representative stands to enable a natural regeneration.
Localities of representative stands (loci typici) with state of protection
of the natural vegetation
Esthonia: reserves in the west of the country.
of characteristic substitute communities worthy of protection
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Most important references (author, year)
Laasimer 1965
Compiled by
Z. Neuhäuslová and H. Wagner based on documents by V.I. Vasilevič, with completions by J. Sultson
