Walker - 1967 - A geography of Italy

THE ALPS
rugged and the valleys, though often steep, are less restricted; most of the cols
connecting the Val Seriana and the Val Brembana are also developed on marls.
The limestones, on whose surface karst phenomena frequently occur, are extensively
forested while the marls are used for hay and hardy crops. The main ridge
of the Alpi Orobie, topping 3000m in Pizzo di Coca, is carved in gneisses, micaschists
and Permian conglomerates; the same rocks extend over wide areas to the
north o f the Brescian Pre-Alps, which are structurally a continuation o f the
Bergamasque Pre-Alps (fig. 22).
The crystalline zone o f the Alpine core is deeply trenched by the Tonale fault
line into which numerous transverse valleys from the main watershed find their
way. Prolonged denudation punctuated by rejuvenation has produced a complex
drainage pattern with several captures; thus the upper Oglio once flowed into the
Adda through the Aprica col but was captured by the Ogho as it cut back northwards.
The commonest rocks exposed are gneisses, mica-schists and granites
with occasional outcrops oipietre verdi’, any tendency towards differential erosion
is usually reduced to insignificance by the overwhelming ferocity o f glacial action.
The Adula and Bernina (4055m) groups on the main watershed and the Ortles
(3763m) and Adamello-Presanella groups to the south o f it are high enough to
support extensively permanent snowfields and a number o f small glaciers.
In the case o f the western Alps a distinction was made between the agriculture
of the deep, low-level valleys and that o f the higher valleys; this distinction is
equally valid for the central Alps. In the Valtellina, for example, fodder, cereals
and fruit, often grown with the assistance o f irrigation, cover much o f the alluvial
valley floor; on the lower solatia slopes the chestnut zone has been widely
replaced by terraced vineyards whose names and reputations are well known in
the industry. Further up, the slopes are shared between chestnut woodlands and
small peasant holdings created and maintained at immense pains; such units,
many of which are now being abandoned, clearly reflect the population pressures
of the recent past. Except on the lowest slopes, where hardy crops and hay are
cultivated, the ombria side o f the Valtellina is clothed with coniferous forests
broken here and there by high pastures. Outside the main valleys and the lake
shores (where delicate tree crops assume a modest importance) the rural economy
depends on forestry and animal rearing. Transhumance is on the decline generally
and is now in the hands o f professional cowherds.
The main industrial resources o f the area lie in its water and in its hydroelectric
power (21% o f Italy’s output in 1964). Both have been fully exploited,
although the Alps themselves get less than their fair share o f the benefits. The
traditional extractive industries are still o f some importance in the Pre-Alps; the
cement industry is served by a number o f large quarries, and lead and fluorspar
are mined in the Val Brembana and the Val Trompia. Metal working has been a
traditional activity in Brescia province since the Middle Ages and there are still a
number of small iron works in operation using local ore. The most productive
mining zone is in the Val di Scalve and the biggest iron and steel plant is sited at
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