Alpine Parasteppic Grasslands of the High Friulian Plain

The steppe-like, dry grasslands found to the south of the Carnic and Julian pre-Alps at altitudes up to 300 m are in one of the wettest parts of Europe, but the gravelly soils are so permeable that most of the precipitation rapidly percolates away. The vegetation is known locally as ‘magredi’ (in the Friulian language), which is derived from the Latin term ‘mager’ suggesting an agriculturally poor area. It can be broadly divided in to three successional types: 1. The typical community characterised by Globularia cordifolia and the endemic Centaurea dichroatha (Asteraceae), 2. An intermediate community characterized by Schoenus nigricans and Chrysopogon gryllus and 3. A mature community characterized by Chrysopogon gryllus and the endemic Chamaecytisus purpureus (Fabaceae). These grasslands have considerable phytogeographical interest in that they support eastern (Illyrian and Pontic) elements, Alpic elements and endemic elements. The Illyrian species close to their northern and western limits include Crepis froelichiana, Dorycnium pentaphyllunum, Genista sericea, Knautia illyrica, Potentilla australis, Satureja variegata and Seseli gouanii. Some of the endemic or subendemic taxa include Brassica glabrescens (Brassicaceae), Buphthalmum salicifolium (Asteraceae), Campanula caespitosa (Campanulaceae), Carex mucronata (Cyperaceae), Centaurea nigrescens (Asteraceae), Daphne cneorum (Thymelaeaceae), Euphorbia triflora ssp. kerneri (Euphorbiaceae), Euphrasia cuspidata (Orobanchaceae), Hieracium porrifolium (Asteraceae), Knautia ressmannii (Dipsacaceae), Matthiola carnica (Brassicaceae) and Rhinanthus freynii (Orobanchaceae).

Alpine Scree Vegetation

In the Alps a number of scree vegetation types have been recognized. On limestone and dolomite scree in the high alpine and nival belts Thlaspi rotundifolium oftencharacterizes the vegetation. Other local dominants may include Achillea atrata, Campanula cochlearifolia, Doronicum grandiflorum, Gymnocarpum robertianum, Leucanthemum atrata, Rumex scutatus and Saxifraga oppositifolia. The many alpine endemics or near endemics found in this type of vegetation include Campanula cespitosa (Campanulaceae), Galium helveticum (Rubiaceae), Papaver alpinum (Papaveraceae), Saxifraga biflora (Saxifragaceae), Valeriana supina (Valerianaceae), Viola cacarata and V. cenisia (Violaceae). Scree vegetation characterized by the alpine endemic Leontodon montanus (Asteraceae) occurs on finer more moist, clay-slate screes with quantities of interstitial fine soil. Associate species include Ranunculus parnassifolius and the alpine endemic Saxifraga biflora subsp. macropetala (Saxifagaceae). On the other hand, some of the limestone screes in the subalpine zone with fine-moist soil are characterized by Petasites paradoxus. Other characteristic species here include Valeriana montana and the alpine endemic Adenostyles glabra var. calcarea (Asteraceae) and Poa cenisia (Poaceae). Surprisingly acidic, silicate scree tends to be more favourable to plant growth than limestone scree since it usually supports quantities of sandy soil that has a better water holding capacity than the soils of limestone screes. The main plant formation of these acidic screes is characterized by the alpine endemic Androsace alpina (Primulaceae). Other dominants may include Geum reptans and Trisetum spicatum, while typical endemic taxa include Gentiana bavarica var. subacaulis (Gentianaceae) and Saxifraga sequieri (Saxifragaceae). On silicate screes poor in humus, Oxygria digyna together with Adenostyles tomentosa and the alpine endemic Cerastium pedunculatum (Caryophyllaceae) may become conspicuous. Finally, on calcareous slate slopes, which are thought to have characteristic in between limestone and silicate screes, the alpine endemic Draba hoppeana (Brassicaceae) is likely to become the most characteristic species. Others include Artemisia genipi, Crepis rhaetica, Draba fladnicensis and the alpine endemic Pedicularis asplenifolia (Orobanchaceae).

Alpine Grasslands on Carbonate Soils

Most noteworthy of these alpine grasslands are the blue moorgrass (Sesleria albicans)evergreen sedge (Carex sempervirens)formations which is particularly well represented on limestone rocks of the eastern Alps. This formation provides some of the most spectacular flower shows of the alpine and sub alpine zones. Other characteristic species depending on location include the famous Edelweiss (Leontopodium alpinum) together with Anthyllis alpestris, Carduus defloratus, Carex humilis, Erica herbacea, Helianthemum alpestre, H. grandiflorum, Pedicularis verticillata, Phyteuma obiculare, Polygala chamaebuxus and endemic or near endemic species like Alchemilla hoppeana (Rosaceae), Carex austroalpina (Cyperaceae) and Pedicularis rostrato-capitata (Orobanchaceae). In places where the snow clears early exposing areas to cold winds Sesleria albicans can still survive but a number of the other associates are replaced by cushion forming plants. One of the most characteristic of these is the cushion-sedge (Carex firma). Apparently this species is highly economic with the nutrients of its self-made humus contained within its cushions, and can even re-root into its dead remains. Other cushion plants and low-growing rosette species found under these conditions may include Chamorchis alpina, Crepis kerneri, Gentiana clusii and Saxifraga caesia. Other alpine calcareous grasslands types found in the Alps include rusty sedge (Carex ferruginea) meadows in the outer Alps and the violet fescue (Festuca violacea) pastures of the northern Swiss Alps.

Alpine Acid Grassland

On crystalline rock and other lime-deficient substrates crocked sedge (Carex curvula) often predominates. The olive-green leaves of this species give the sward a perpetual autumn look and it has very low grazing value. Other flowering plants are not particularly well represented but still add welcome colour to the sward with the yellows of Arnica montana, Leontodon helveticus, Potentilla aurea and Senecio incanus ssp. carniolicus, and the blues of Campanula barbata, Veronica bellidioides and species of Phyteuma. In other acidic areas, such as the slopes near Puschlav the alpine, endemic grass Festuca varia (Poaceae) becomes widespread. A common companion is Carex sempervirens. In the lower alpine and sub-alpine belts Nardus strictus (mat grass) often becomes the dominant grass of acidic areas.

Alpine and Subalpine Heaths

In the Alps these can be divided into at least three separate associations. In the true alpine zone only a few woody species are able to survive. One of the most important of these is the prostrate azalea Loiseleuria procumbens and a few dwarf willows. The herbaceous willow Salix herbacea may occur in protected snow coombs for example. Creeping azalea heaths are often exposed to strong winds and may not gain a covering of protective snow during the winter and so can experience temperatures down to -40o C. In slightly less exposed areas other dwarf shrubs such as Arctostaphylos uva-ursi and Vaccinium uliginosum may be present. At lower levels, in the subalpine zone, Empetrum hermaphroditum (mountain cranberry) and Vaccinium uliginosum (bog bilberry) can form distinct heaths, but these formations are often protected by a covering on snow in winter, and as a result can grow to their full stature during the growing season, but many stands are now heavily grazed. More conspicuous in the sub alpine zone are alpenrose (Rhododendron ferrugineum) heaths with their displays of bright red flowers.

Alpine Naked Rush-Dwarf Shrub Heath

In the Alps this is typified by Elyna myosuroides. Characteristics species here include Carex atrata, Dianthus glacialis, Erigeron uniflorus, Potentilla atrata, Saussurea alpina and the endemic or near endemic Oxytropis jacquinii (Fabaceae) and Sesleria sphaerocephala (Poaceae).

Alpine and Subalpine Rock and Boulder Formations

Although lichens and certain bryophytes can colonize bare rock, phanerogams are largely restricted to cracks and crevices. These so-called chasmophytic (crevice dwelling) species include a number of different associations depending on rock type and environmental conditions and typically include a rich variety of endemic taxa. In the Alps Potentilla caulescens is often the main character species of carbonate rock in the true alpine zone. Among its associates are various endemic or near endemic species like Carex mucronata (Cyperaceae), Minuartia rupestris (Caryophyllaceae) and Valeriana saxatilis (Valerianaceae). On the hard limestone of the Swiss Jura the endemic Androsace helvetica (Primulaceae) can also become characteristic with associates such as the endemic Draba ladina (Brassicaceae). Potentilla caulescens can also be a feature of subalpine carbonate rocks. Its associates may include Festuca stenantha and Hieracium humile. On silicate rocks in the Alps Androsace vandellii often characterizes the chasmophytic flora together with species such as the endemic or near endemic Erigeron gaudinii (Asteraceae), Eritrichum nanum (Boraginaceae) and Minuartia cherlerioides (Caryophyllaceae). At lower altitudes Primula hirsutum can become one of the main silicate rock fissure species, while the endemic Phyteuma scheuchzeri (Campanulaceae) is likely to be one of its associates. Many other chasmophytic formations have been described particularly in the Carpathian Mountains.

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