Title
Colchic lowland to submontane mixed oak forests (Quercus imeretina, Quercus hartwissiana, Zelkova carpinifolia, Carpinus betulus, Castanea sativa, Fagus sylvatica subsp. orientalis) with evergreen understorey species (Rhododendron ponticum, Prunus laurocerasus), alternating with oak and hornbeam-oak forests (Quercus iberica, Carpinus betulus) in the submontane belt
Geographical distribution
Country/territory
Georgia: Colchic low plain, foothills and below slope sites of mountains
Scientific names of main plant communities and their most common synonyms (with author citation)
Quercetum imeretina azaleosum, Quercetum imeretina hypericosum (Machatadze, 1964); Castanetum azaleosum, Castanetum rhododendrosum, Castanetum laurocerasosum (Doluchanov, 1953).
Structural feature of the main community(ies) (layers, life-forms, etc.)
The natural vegetation is represented by various summer-green broad-leaved forest communities whereby oak and chestnut mixed forests dominate. Colchic endemics as well as species with a limited range play an important role in the vegetation covering. The often two-layered tree layer consists of different, sometimes endemic oak species (Quercus imeretina), Zelkova carpinifolia, Carpinus betulus, Castanea sativa, Fagus sylvatica subsp. orientalis and admixtures of Caucasian and European-Caucasian woody plants (Acer cappadocicum, Sorbus torminalis, Fraxinus excelsior, Tilia begoniifolia). Evergreen species are present in the undergrowth, while in the herb layer Colchic and Colchic-Hyrcanian species are typical.
Dominant and most frequent species in different layers
Tree layer
Quercus imeretina, Quercus hartwissiana, Zelkova carpinifolia, Carpinus betulus, Castanea sativa, Fagus sylvatica subsp. orientalis, Ulmus elliptica, Tilia ledebourii, Tilia begoniifolia, locally Diospyros lotus, Alnus barbata
Shrub layer
Rhododendron ponticum, Rhododendron luteum, Rhododendron ungernii, Prunus laurocerasus, Daphne pontica, Staphylea colchica, Buxus colchica, Ilex colchica, Hypericum xylosteifolium, Ruscus colchicus, Vaccinium arctostaphylos, Epigaea gaultherioides
Lianas
Hedera colchica, Hedera helix, Smilax excelsa, Vitis vinifera subsp. sylvestris, Periploca graeca, Clematis vitalba, Humulus lupulus, Dioscorea caucasica
Herb layer
Iris colchica, Dryopteris dilatata, Dryopteris aemula, Brachypodium sylvaticum, Brachypodium pinnatum subsp. rupestre, Epimedium colchicum, Trachystemon orientalis, Symphytum ibericum, Oplismenus undulatifolius, Athyrium filix-femina, Blechnum spicant, Polystichum woronowii, Polypodium cambricum, Cardamine impatiens
Moss layer (incl. lichens)
no details
Diagnostically important species
Quercus imeretina, Tilia ledebourii; Rhododendron ponticum, Staphylea colchica, Hypericum xylosteifolium, Ruscus colchicus, Hedera colchica; Iris colchica, Dryopteris dilatata, Dryopteris aemula; Hyrrcanian-Colchic species: Pterocarya pterocarpa, Zelkova carpinifolia, Polystichum woronowii; euxinic species with further radiation: Quercus hartwissiana, Prunus laurocerasus, Rhododendron luteum, Daphne pontica, Trachystemon orientalis
Ecological variants
Epiphytes (Usnea barbata, Neckera spp., polypodium spp.) are distributed in stands with high air humidity. Moist forms of Quercus imeretina forests with Smilax excelsa; dry forms with Carpinus orientalis, Zelkova carpinifolia.
Geographical variants (geogr. differential species)
No details
Natural accompanying vegetation (most important units in complex with the name giving mapping unit, scientific names)
Coastal vegetation (rock, gravel); Celtis australis-Ficus carica community; in submontane areas oak and hornbeam-oak forests (Quercus iberica, Carpinus betulus), hornbeam-beech (Fagus sylvatica subsp. orientalis, Carpinus betulus) and hornbeam-chestnut forests (Castanea sativa, Carpinus betulus); on humus carbonate soils forests with Buxus colchica; Prunus laurocerasus stands on seaward and particularly moist slopes; Alnus barbata swamp forests and Pterocarya pterocarpa alluvial forests, willow scrub (Salix alba subsp. micans, Salix pantosericea).
Adjoining climax and permanent vegetation (with numbers of mapping units)
Oriental beech forests (F163), oak forests (F169), alder carrs (T3).
Land use, substitute communities
forestry (substitute communities, plantations of economic tree-species, scrub)
After forest cutting the luxuriantly developing evergreen undergrowth hinders tree rejuvenation. In weakly disrupted semi-natural communities oak, zelkova, chestnut and beech dominate, while in disrupted and secondary stands hornbeam and alder are more frequent, and the coverage of the liana layer increases; Prunus laurocerasus thickets, Rhododendron stands. Plantation of eucalyptus, palms, magnolias and oleander.
grassland (meadows, pastures, herb-rich communities)
Meadows and pastures, grasslands with Calamagrostis epigejos, Pteridium aquilinum subsp. brevipes stands etc.
arable land (characteristic weed communities)
Tea and citrus fruit plantations (mandarins, oranges etc.), also tung tree and Laurus nobilis plantations, tobacco, corn, cereal, fruit and vegetable cultivation as well as vineyards.
settlements (typical ruderal vegetation)
Ruderal communities with Lepidium texanum, Pteridium aquilinum subsp. brevipes, Conyza bonariensis, Paspalum paspalodes, Sorghum halepense, Cynodon dactylon, Tradescantia spp., Galinsoga spec.
Site conditions of the mapping unit
Landscape type, geomorphology
lowland plains, slopes, and sometimes ravines
Altitudinal belt and/or altitudinal range
lowland to submontane, 0 to 500 (600)m
Geology (bedrock)
Quaternary sands, clays; Pliocene and Miocene conglomerates, sandstone, clays; Miocene limestone; clays and sands (Oligocene-Lower Miocene); andesite from the Middle Eocene (Tertiary)
soil type, also the depth of fine textured earth (soil), stone content; (international nomenclature)
podzolic soils, yellow and red earth, montane brown, partly yellow-brown soils (brown soils); (orthic acrisols; xanthic, rhodic and haplic ferralsols; cambisols)
soil texture
loamy, clayey, sandy
soil moisture, water balance
fresh to moderately dry
soil reaction
acid to moderately acid
soil fertility
mesotrophic, meso-eutrophic
Climate incl. local climate
climate type (following Walter & Lieth)
V
average annual temperature
13-14 °C
average annual precipitation
1100-2700 mm (as much as 3500 mm in the south-western part)
average temperature of the warmest month
July/August 22,5-24 °C
average temperature of the coldest month
January 4,5-6,5 °C
local climate or other climatic peculiarities
moist-warm, nearly subtropical climate. Relative humidity influenced here and there by foehn or briza-winds. Low yearly amplitude of the average monthly temperatures (15-19 °C).
Importance for nature protection
Present state and development trend of natural vegetation (degree of endangerment)
The natural vegetation of the lowland plains and the hilly foothills has been destroyed to a large extent. Remnants of semi-natural forest vegetation have survived best at mountain slopes where they are very worthy of protection. Areas inaccessible until now are threatened by infrastructure development processes (roadway building) and pasturing.
endangered communities, species worthy of protection in natural vegetation
All nearly-natural forest fragments; sites of colchic endemics and of relict species.
causes of endangerment
Clear cutting, forest grazing, agricultural use, settlements, tourism.
required measures for protection and restitution
Establishment of new, modern nature reserves (national parks etc.) in the autonomous regions of Abkhazia and Adjaria.
Localities of representative stands (loci typici) with state of protection
of the natural vegetation
Georgia: Zelkova oak forest with Quercus imeretina (nature reserve Adžamet); Stands of nearly-natural mixed broadleaved forests of the Colchic hill country (nature reserve Picanda-Mjusser).
of characteristic substitute communities worthy of protection
no details
Most important references (author, year)
Doluchanov 1980; Golicin 1939; Grossgejm 1948; Kolakovskij 1961; Koževnikov 1937; Machatadze 1964; Mandžavidze 1982; Nachucrišvili 1999; Sachokia 1980
Compiled by
Z. Neuhäuslová based on documents by A.G. Doluchanov, completed by N. Zazanašvili and G. Nachucrišvili
