Mediterranean mountain Betula and Populus tremula woodland on mineral soils

This habitat includes a variety of deciduous birch and aspen woodlands growing at the sub-alpine level in the high mountain ranges of southern Europe. In such situations, the short growing season, the prevalence of frost and high exposure limit both the possible dominants and the structure of the woodland. Silicate soils predominate, strongly acidic and often podzolised.

 In the Pyrenees and the more humid Cantabrian mountains of Spain, there are woodlands in the subalpine belt with canopies of other birches of variously contested taxonomy: B. pubescens subsp. pubescens (= B. carpatica), B. pubescens subsp. celtberica (B. celtiberica) and B. pendula subsp. fontqueri (B. fontqueri). Here birch is often a secondary invader, colonising spontaneously after avalanches, fire and clear cutting, but it can form more permanent woodlands on boulder scree where there is much winter snow accumulation.

Betula pendula forms extensive belts of woodland on rapidly eroding soils at the upper forest limit on the high mountains of Corsica

Between 1400 and 2000m on the north-eastern slopes of Etna in Sicily, an open canopy of B. aetnensis develops over volcanic cinders in a severe montane climate subject to frequent volcanic events such as ash rains. Pinus nigra, Quercus dalechampii and Q. congesta occur occasionally with a species-poor field layer of Pteridium aquilinum, Festuca circummediterranea, Achillea ligustica, Genista aetnensis, Astragalus siculus, Tanacetum siculum and Carlina nebrodensis.

This habitat also includes high mountain woodlands dominated by Populus tremula. On Etna, this tree dominates in small humid valley woodlands above 900m where there is a quite rich mesophytic flora including Brachypodium sylvaticum, Lathyrus pratensis, Daphne laureola and Agropyron panormitanum.

Relict aspen forests can also be found on deep colluvial soils in humid foothill and mountain gorges from 600-1500m in the central and southern Apennines. There distinctive associates are Acer obtusatum, Laburnum anagyroides, Sorbus aria, Euonymus latifolius, Prunus avium, Lonicera etrusca, Rosa arvensis, R. agrestris, Rubus hirtus, Daphne laureola and Chamaecytisus hirsutus with Sanicula europaea, Primula vulgaris, Euphorbia amygdaloides, Fragaria vesca and Melica uniflora.

Indicators of quality:

• Woodland permanent not a successional stage
• Dominance by either birch or aspen
• Presence of the distinctive woody associates and field layer

Synthesis of Red List assessment

Confidence in the assessment

Pressures and threats