DOLOMITES - Annexes 2-8 - Provincia di Udine

NOMINATION OF THE DOLOMITES FOR INSCRIPTION ON THE WORLD NATURAL HERITAGE LIST UNESCO
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shrubs, fairly characteristic in the Dolomite landscape to the point where dwarf mountain pine represents
one of the most peculiar and most important species in terms of quantity, include not only
mugo pines, but also rhododendrons, green alder woods and various types of pioneer willow woods.
The Alpine belt is located higher in elevation, above the tree and shrub line where the primary prairies
begin. This belt refers to all the types of discontinuous plant life in the higher elevations (cliffs,
detritus, and snowy valleys). Above the elevation where there is perennial snow cover, the presence
of plant life is sporadic and is often represented only by cryptogams (mosses and lichens). We might
also mention here types of so-called azonal plants, since they are particularly related to ecological
conditions, regardless of altitude. This is true of the riparian woods in the vicinity of streams and a
large part of the Scots pine and/or Austrian pine woods. In the Dolomite area, there are no significant
examples of out-of-area plant life, namely the expression of ecological climates and conditions
of past eras or other geographic territories. This category might include several arid-steppe realms,
located on the steep slopes in the innermost continental valleys.
Woods and shrub forests
In the residual flood areas of the valley floor, potentially very hospitable to mixed forests of oak and
horn-beam (widespread in Central Europe), human settlement and agricultural areas have very nearly
replaced forest regions. Possible relict species (English oak and common alder) therefore hold exceptional
bio-geographical value and are protected as biotopes, especially in the Alto Adige (Provincia
Autonoma di Bolzano). The presence of black locust, a North American species well naturalized
in these regions, is a good indicator of the decay of these flatlands and hill habitats. Woods are well
conserved on the steep slopes that characterize the valleys of the outermost Dolomite area. Mixed
manna ash and horn-beam woods, with prevalent hop-hornbeam and several thermophilic shrubs
and shrubs from the sub-Mediterranean zones occupy large surfaces. In the more suitable habitats,
these can grow even up to 1,000 to 1,200 meters. In the more continental realms (with a distinct gradient
from south east to north west) of these coppices – whose trees are still used for firewood – there
is a significant increase in pubescent oak. Oak is more commonly localized on dry and acidic soil and
forms communities, generally mixed, in several Trentino valleys on soils whose origin is the breakdown
of silica rocks, sometimes even in the montane belt. In the easternmost Dolomite mountains,
oceanic influences lead to an important presence of Austrian pine, which thrives and has pushed all
the way to the Cordevole and Mis valleys. The distribution of Scots pine is also noteworthy, especially
in the innermost continental realms or on the Dolomite substrates as communities and colonies
on gravely soil. In the montane belt more fertile woods develop and hold more interest for the
forestry industry. The general makeup of the communities is heavily influenced by the climate. Outside,
toward the Prealps and in the zones of higher rainfall (meso-Alpine region), pure and mixed
beech woods dominate, while conifers increase farther inward, thriving in the more continental climate
until the beech trees disappear. In a wide stretch of the Dolomite territory, very widespread
(and very beautiful, and sometimes very valuable from a naturalistic viewpoint) are the mixed woods
with a predominance of silver fir. Primiero, Val di Fiemme and Lagorai, Caiada and Val del Grisol
(Longarone area), Auronzo, left-bank Piave Dolomites, Comelico and Carnia are very beautiful forest
districts. The Norway spruce, one of the most distinctive features of the Dolomite landscape, was
heavily planted by man, but actually finds better conditions in either the altimontane or the sup- Alpine
belts, above the fir coppices, or in the innermost valleys in which red fir woods dominate unchallenged
over other types of trees. Spruce has been replaced only on the steeper and drier slopes,
on the primitive gravely soils, by Scots pine coppices. Considering the complex orographical features
and the numerous microclimates of the Dolomite region, it would be presumptuous to name the
diverse situations that can be created (a characteristic of the Dolomite plant landscape is in fact its
variegated and sometimes quite unpredictable nature).