Title
Transcaucasian oak forests (Quercus iberica), hornbeam-oak forests (Quercus iberica, Carpinus betulus) and Oriental hornbeam-oak forests (Quercus iberica, Carpinus orientalis), with Acer cappadocicum, Sorbus torminalis, partly in combination with shibliak communities (scrub
Geographical distribution
Country/territory
Russia: Daghestan; Georgia: central and eastern part; Armenia; Azerbaijan
area frequency
12 polygons .
Scientific names of main plant communities and their most common synonyms (with author citation)
Quercion ibericae sensu Doluchanov.
Structural feature of the main community(ies) (layers, life-forms, etc.)
Because of the broad ecological amplitude of their constituent tree species, Quercus iberica forests are varied both structurally and with respect to their species assemblages. The unit consists of a complex of three main types: pure oak, hornbeam-oak and oriental hornbeam-oak forests. Occasionally there are oak forests with a large proportion of Fraxinus excelsior and/or other tree species.a) Hornbeam-oak forests occupy the fresher and cooler sites near to the upper distribution limit and are more productive. The upper tree layer (Quercus iberica, sometimes with admixtures of Fraxinus excelsior and other tree species) is 20-25 m, and rarely 28 m tall. Unlike Quercus petraea, the maximum height of Quercus iberica seldom exceeds 30 m. The hornbeam reaches the same height as the oak does.b) Oriental hornbeam-oak forests are characteristic for drier and warmer sites, mostly at lower altitudes; they are less productive. The upper tree layer, formed by Quercus iberica, is 12-18 m here, and rarely 20 m tall. The oriental hornbeam layer is much lower (5-8 m, rarely 12 m tall ).c) In monodominant oak forests the height of the tree layer is 14-22 m. The shrub layer is absent or can be very differently formed.The herb layer consists above all of species of Caucasian summer-green forests. In stony habitats local endemics are frequent. It is also geographically differentiated (see point 'Geographic Form').
Dominant and most frequent species in different layers
Tree layer
a-c) Quercus iberica, Carpinus betulus, Carpinus orientalis, with different admixture of Fraxinus excelsior, Acer cappadocicum, Acer campestre, Sorbus torminalis, Acer platanoides, Prunus avium, Pyrus caucasica, Malus sylvestris subsp. orientalis
Shrub layer
a) Cornus mas, Cornus sanguinea subsp. australis, Corylus avellana, Euonymus latifolia, Euonymus europaea, Frangula alnus, Prunus divaricata, Prunus mahaleb, Mespilus germanica, Crataegus-species;
b) Pyracantha coccinea, Ligustrum vulgare, Lonicera iberica, Rhus coriaria, Euonymus verrucosa, Rhamnus spathulifolia, Spiraea crenata, Rosa corymbifera, Rosa canina, Juniperus communis subsp. oblonga
Herb layer
a) Festuca drymeja, Poa nemoralis, Polygonatum glaberrimum, Galium odoratum, Sanicula europaea, Vicia crocea, Mycelis muralis, Galanthus woronowii, Galanthus caucasicus, Scilla siberica, Corydalis caucasica, Asplenium adiantum-nigrum, at more open sites: Brachypodium sylvaticum, Platanthera chlorantha, Campanula rapunculoides subsp. cordifolia, Veronica peduncularis, Solidago virgaurea, Serratula quinquefolia, Physospermum cornubiense, Lathyrus roseus, Vincetoxicum scandens;
b) on dry sites: Carex humilis, Carex digitata, Achillea biserrata, Tanacetum partheniifolium, Campanula alliariifolia, Laser trilobum, Silene italica, Argyrolobium biebersteinii, Dorycnium graecum, Dictamnus caucasicus
Moss layer (incl. lichens)
No details
Diagnostically important species
Quercus iberica, Carpinus betulus, Carpinus orientalis, Acer cappadocicum, Sorbus torminalis, Pyrus caucasica as well as species under point Geographical variants’, Lonicera iberica, Genista dracunculoides, Chamaecytisus ruthenicus, Aristolochia iberica, Cyclamen coum subsp. caucasicum, Helleborus caucasicus, Polygonatum glaberrimum, Argyrolobium biebersteinii, Primula woronowii, Physospermum cornubiense, Pimpinella tripartita, Convallaria transcaucasica, Clinopodium umbrosum, Veronica peduncularis, Ophrys oestrifera
Ecological variants
Different forms depending on altitude, exposure, slope inclination as well as depth, trophy and water balance of the soils.
Geographical variants (geogr. differential species)
In the eastern part of the range Acer hyrcanum, Acer monspessulanum subsp. ibericum and Celtis caucasica occur. Species with Hyrcanian-Iranian distribution strongholds are typical for the Talysh: Acer hyrcanum, Pyrus hyrcana, Pyrus grossheimii, Carpinus schuschaensis, Cornus meyeri, Frangula grandiflora, Rubus hyrcanus, Danae racemosa, Amblyocarpum inuloides, Paeonia mlokosewitschii, Lilium ledebourii, Galanthus transcaucasicus, Scilla caucasica amongst others. In Quercus iberica forests of southeast Transcaucasia many species of the Anatolian (Asia Minor) forest flora occur: Quercus boissieri, Amygdalus zangezura, Pyrus raddeana, Pyrus voronovii, Acer monspessulanum subsp. ibericum, Euonymus latifolia, Euonymus velutina, Centaurea karabaghensis, Bupleurum polyphyllum, Iris imbricata, Gagea caroli-kochii etc..
Natural accompanying vegetation (most important units in complex with the name giving mapping unit, scientific names)
In the south, small incidences of open oak forests (Quercus boissieri) of the mountains; in the semiarid climate complex there are formations with xerophilic open forests, arid scrub, thorn-cushion vegetation and mountain steppes. alluvial and lowland forests with Quercus pedunculiflora (U22).
Adjoining climax and permanent vegetation (with numbers of mapping units)
krummholz and open woodlands (C43, C44, C46), fir and mixed fir forests (D32, D33), Caucasian pine forests (D64), Oriental beech forests (F164, F165, F166), Caucasian mixed hornbeam-oak forests (F167, F171, F172), downy oak forests (G62), Hyrcanian forests (H2, H3), open juniper woodlands (K33), forest steppes (L8), steppes (M4, M11, M17, M18a), thorn-cushion vegetation (N5, N7), deserts (O7, O9, O10), brackish water reed vegetation (R3), alluvial forests (U21, U22).
Land use, substitute communities
forestry (substitute communities, plantations of economic tree-species, scrub)
Oak-hornbeam and oriental hornbeam low forest, deciduous and coniferous plantations, shiblyak scrub with Paliurus spina-christi, Juniperus foetidissima.
grassland (meadows, pastures, herb-rich communities)
Pastures (dry grassland with Bothriochloa ischaemum).
arable land (characteristic weed communities)
Vineyards and orchards, cereal fields.
settlements (typical ruderal vegetation)
No details
Site conditions of the mapping unit
Landscape type, geomorphology
Low mountains and foothills of the eastern Greater and Lesser Caucasus, shallow-soiled steep slopes (scarps).
Altitudinal belt and/or altitudinal range
(colline) submontane to montane; (300-400) in continental regions 600/700 to 1400 m (rarely as high as 1700 m)
Geology (bedrock)
marine sedimentary rocks of different composition, often limestone and chalky clay (Tertiary, Cretaceous, Jurassic), basic volcanic rocks (Quaternary, Tertiary), fluviatile sediments (Quaternary)
soil type, also the depth of fine textured earth (soil), stone content; (international nomenclature)
grey-brown, often shallow and stone-rich mountain-forest soils, humus-carbonate soils (rendzines), black earth-like and chestnut mountain-forest soils; (dystric and chromic cambisols; chromic luvisols; rendzic leptosols)
soil texture
loamy, clayey, often stony
soil moisture, water balance
fresh to dry
soil reaction
acidic to neutral
soil fertility
mesotrophic, meso-eutrophic
Climate incl. local climate
climate type (following Walter & Lieth)
VI(IV), X
average annual temperature
around 13 EC at the lower limit, around 6 EC at the upper limit
average annual precipitation
450-750 mm (here and there as much as 1100 mm)
average temperature of the warmest month
22-23 EC at the lower limit, 16-17 EC at the upper limit
average temperature of the coldest month
0-1 EC at the lower limit in east-trans-Caucasia, -5 to ‑2EC at the upper limit
local climate or other climatic peculiarities
The yearly amplitude of the average monthly temperature is: 22-24 EC in east trans-Caucasia; yearly sums of temperature above 10 EC at lower sites around 4000 EC, at medium altitudes around 3000 EC, at the upper limit around 2000 EC.
Importance for nature protection
Present state and development trend of natural vegetation (degree of endangerment)
Quercus iberica oak forests have been cleared for the most part or degraded by use, and as such only a few semi-natural stands still remain.
endangered communities, species worthy of protection in natural vegetation
Relict occurrences in the Caucasus: Taxus baccata.
causes of endangerment
Low forest use, clearing, livestock grazing, crop field usage, settlements.
required measures for protection and restitution
Designation of conservation areas for the rare semi-natural remnants, since the mapping unit is hardly represented at all in national parks or nature reserves.
Localities of representative stands (loci typici) with state of protection
of the natural vegetation
Georgia: in the districts of Achmeta, Duscheti and Borñomi; Azerbaijan: Zapovednik Ismayili, nearly-natural fragments in the Talysch-mountains; south Armenia: Zangezur-mountains.
of characteristic substitute communities worthy of protection
No details
Most important references (author, year)
Bachsoliani 1972; Doluchanov 1955; Doluchanov 1974a; Doluchanov 1974b; Kolakovskij 1961; Machatadze 1941; Prilipko 1954; Sachokia 1980
Compiled by
Z. Neuhäuslová based on documents by A.G. Doluchanov and Ju.R. Šeljag-Sosonko, completed by U. Bohn
