Mountain Region of the Alps |
Many writers take the growth of grain as the characteristic of the mountain region;
but so many varieties of all the common species are in cultivation, and these have such different climatal requirements, that
they do not afford a factory criterion.
A more natural limit is afforded by the presence of the chief deciduous
trees -- oak, beech, ash and sycamore
maple. These do not reach exactly to the same elevation, nor are they often found growing together; but their upper limit
corresponds accurately enough to the change from a temperate to a colder climate that is further proved by a change in the wild
herbaceous vegetation. This limit usually lies about 1200 m above the sea on the north side
of the Alps, but on the southern slopes it often rises to 1500 m, sometimes even to 1700
m.
It must not be supposed that this region is always marked by the presence of the characteristic trees. The interference of man
has in many districts almost extirpated them, and, excepting the beech forests of the Austrian Alps, a considerable wood of deciduous trees is scarcely anywhere to be found. In many districts where
such woods once existed, their place has been occupied by the Scots pine and
Norway spruce, which suffer less from the ravages of goats, the worst
enemies of tree vegetation. The mean annual temperature of this region differs little from that of the British Islands; but the climatal conditions are widely different. Here snow
usually lies for several months, till it gives place to a spring and summer considerably warmer than the average of British
seasons.
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