Title
Downy oak forests (Quercus pubescens) with Campanula bononiensis, partly with Saponaria ocymoides in combination with pine dry forests (Pinus sylvestris) in the west Inner Alps
Geographical distribution
Country/territory
Switzerland: upper and central Valais along the Rhône between Visp and Martigny; Italy: Aosta valley
area frequency
2 polygons.
Scientific names of main plant communities and their most common synonyms (with author citation)
Campanulo bononiensis-Quercetum pubescentis Braun-Blanquet 1961; Arabidi turritae-Quercetum pubescentis Ellenberg & Klötzli 1972 p.p., Campanulo trachelii-Quercetum pubescentis Burnand 1976, Saponario-Quercetum pubescentis Burnand 1976; Campanulo medii-Quercetum pubescentis Ubaldi, Zanotti, Puppi, Speranza & Corbetta 1987 (Aosta valley).
Structural feature of the main community(ies) (layers, life-forms, etc.)
The tree layer of the stands is 10-15 m high and consists of Quercus pubescens, Acer opalus and other drought-resistant tree species. In the Valais the proportion of Pinus sylvestris increases to the east and higher up. The shrub layer is sometimes species-rich and dense. Photophilous species often appear in the herb layer. The moss layer is insignificant.
Dominant and most frequent species in different layers
Tree layer
Quercus pubescens, Pinus sylvestris, Acer opalus, Acer campestre, Sorbus aria
Shrub layer
Colutea arborescens, Cornus mas, Cornus sanguinea, Hippocrepis emerus, Juniperus communis, Lonicera xylosteum, Prunus avium, Prunus mahaleb, Ligustrum vulgare, Viburnum lantana, Rhamnus cathartica, Corylus avellana, Crataegus monogyna, Amelanchier ovalis
Herb layer
Carex humilis, Hieracium murorum agg., Teucrium chamaedrys, Galium lucidum, Fragaria vesca, Arato turrita, Saponaria ocymoides, Stachys recta, Campanula bononiensis, Limodorum abortivum, Silene coronaria, Brachypodium pinnatum, Hepatica nobilis, Carex alba, Calamagrostis varia, Polygala chamaebuxus, Sesleria albicans, Epipactis atrorubens
Moss layer (incl. lichens)
Homalothecium lutescens, Hypnum cupressiforme
Diagnostically important species
Quercus pubescens; Cornus mas, Colutea arborescens; Campanula bononiensis, Silene coronaria, Saponaria ocymoides
Ecological variants
In the western valley sections of the Rhone under the influence of humid air masses from Lake Geneva one finds the Campanulo trachelii-Quercetum with numerous mesophytic species and acidic indicators (Campanula trachelium, Mycelis muralis, Dactylis glomerata, Phyteuma betonicifolium, Vicia sepium, Brachypodium sylvaticum). Under more continental conditions in the dry mid-Valais, the Saponario-Quercetum pubescentis with Saponaria ocymoides, Berberis vulgaris and Amelanchier ovalis grows in alternation with pine dry forests. Unlike Pinus sylvestris, Quercus pubescens colonises particularly irradiated sites, but is replaced again at higher altitudes and in basins that tend to attract cold air by Pinus sylvestris. See under 'Natural accompanying vegetation' for information about the further subdivision of the pine forests.
Geographical variants (geogr. differential species)
With sub-Mediterranean species in the Aosta valley: Lonicera etrusca (very rare in Valais), Colutea arborescens.
Natural accompanying vegetation (most important units in complex with the name giving mapping unit, scientific names)
Pine dry forests (cf. K1): Snow heath-pine forest (Erico-Pinetum) usually at shaded slopes or on deep soils; wavy hairgrass-pine forest (Avenello-Pinetum) on dry, shallow silicate soils; spiny restharrow-pine forest (Ononido rotundifoliae-Pinetum) on dry, shallow carbonate sites; bartsia-pine forest (Odontito viscosae-Pinetum) on extremely dry, very porous lime rubble and morainal soils with Onosma helvetica; dry grassland and rock communities; alluvial forests (Salicetum albae, Ulmo-Fraxinetum); sometimes fern-rich acidic humus beech forests (Luzulo niveae-Fagetum); fir forests (particularly on the northern side of the slopes: Galio-Abietetum on weakly acidic brown earths, and otherwise normally Carici albae-Abietetum on lime-rich subsoils); spruce forests of the dry valleys (Erico-Piceetum usually on deep-soiled slope bases of drier-warm lime scree slopes, Melico-Piceetum on dry acidic-soil sites).
Adjoining climax and permanent vegetation (with numbers of mapping units)
larch-pine forests (C19), fir forests (D29), spruce forests (D35), acidophilous oak forests (F17), oak-hornbeam forests (F53), species-poor and species-rich beech- and mixed beech forests (F101, F132), pine forests (K1).
Land use, substitute communities
forestry (substitute communities, plantations of economic tree-species, scrub)
Historically there was forest grazing up to about 1920-1940, downy oak low forest, moderately-high forests consisting of a pine tree layer and a downy oak shrub layer, pure pine forests at lower altitudes as degradation stages of the downy oak forests, scrub communities with Berberis vulgaris, Rosa spp. and Juniperus spp.
grassland (meadows, pastures, herb-rich communities)
Bromus erectus, Koeleria vallesiana dry grasslands. Aosta valley: Koelerio-Onosmetum cinerascentis, Melico-Kochietum prostrata, Thymetum angustani, Echinopsi-Artemisietum.
arable land (characteristic weed communities)
Crop fields, fruit cultivation, vineyards.
settlements (typical ruderal vegetation)
Quarries, gravel pits.
Site conditions of the mapping unit
Landscape type, geomorphology
dry-warm inner Alpine valley slopes and valley floors
Altitudinal belt and/or altitudinal range
colline to montane; 450-1400 m
Geology (bedrock)
base-rich siliceous rock (Palaeozoic); limestone, dolomite, lime-slate (Cretaceous, Jurassic, Triassic)
soil type, also the depth of fine textured earth (soil), stone content; (international nomenclature)
humus carbonate soils, para-humus carbonate soils, limestone-brown soil, partly with dry mull-like mor, stone-rich; (rendzic leptosols; lithic dystric and calcaric cambisols)
soil texture
sandy to stony loam
soil moisture, water balance
moderately dry to very dry
soil reaction
weakly acidic to neutral
soil fertility
oligo-mesotrophic to meso-eutrophic
Climate incl. local climate
climate type (following Walter & Lieth)
IV(VI)2, IV(X), VI(X)1
average annual temperature
8-11 °C
average annual precipitation
450-840 mm
average temperature of the warmest month
July 16-20 °C
average temperature of the coldest month
January -1 to 2 °C
local climate or other climatic peculiarities
high insolation, poor in precipitation, warm local climate.
Importance for nature protection
Present state and development trend of natural vegetation (degree of endangerment)
Historically these heavily used forests with a high proportion of pine have reverted by succession back to downy oak forests. Very rare downy oak forests, which due to their restricted extent and the rare species they harbour are highly worthy of protection.
endangered communities, species worthy of protection in natural vegetation
downy oak forests (also semi-natural), steppe grassland.
causes of endangerment
Air pollution, establishment of gravel pits, occasional fires, formerly grazing.
required measures for protection and restitution
Should be preserved and developed as protection forests and examples of rare forest communities.
Localities of representative stands (loci typici) with state of protection
of the natural vegetation
Switzerland: Ban de Branson (Bannwald, Fully, Valais), Forêt de la Lui (reserve, Fully, Valais).
of characteristic substitute communities worthy of protection
No details
Most important references (author, year)
Burnand 1976; Ellenberg & Klötzli 1972; Ozenda 1988; Plumettaz Clot 1988; Rameau 1997; Steiger, Carraro, Frey & Frick 1998; Ubaldi, Zanotti, Puppi, Speranza & Corbetta 1987
Compiled by
C. Hettwer referring to Burnand 1976 and Steiger et al. 1998, completed by U. Bohn referring to Klötzli (hand written) and Rameau 1997
