Walker - 1967 - A geography of Italy

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VEGETATION
variations in soil and moisture; the oleander is usually restricted to the banks o f
ephemeral torrents while the laurel prefers deep-cut valleys offering moisture
and shade. Gorse, broom and cistus are usually an indication o f siliceous soils.
Macchia, which has made its contribution to the shrubberies o f gardens all over
Europe, is most attractive in spring when the greys and dark greens are cheered
by masses o f predominantly yellow blossom. Left undisturbed it might well
develop the biotic conditions conducive to the regeneration o f the original
forest; unfortunately its meagre resources are repeatedly exploited for grazing,
firewood, tannin, basket material and even as long-term fallow.
In fact, outside Sardinia, the area covered by macchia is small; garrigue (or
the infinite variations between it and macchia) is much more common. It consists
o f an assemblage o f low tufty or bushy plants, rarely providing a complete
cover, and capable o f tolerating thin stony soils, high ground temperatures and
desiccating winds. It may represent the degeneration o f macchia or it may be
the direct successor o f the original forest, but in either case it is generally considered
to be the outcome o f human intervention. Sometimes a few survivors of
the forest, a stone pine or a kermes oak, struggle on, and representatives o f the
forest imdergrowth (gorse, broom, dwarf palms) are common, but thyme,
lavender, rosemary and other aromatic herbs (labiates) constitute the biggest
element. In the absence o f true soils the nature o f the parent rock is o f great
importance; broom, gorse, lavender and bramble flourish on siliceous soils while
rosemary, thyme and cistus prefer a calcareous parent rock. Garrigue is o f
meagre value as pasture and repeated grazing tends to eliminate those plants
most acceptable to sheep and goats. In some areas, for example the M m ge o f
Apulia, this process o f deterioration by animal selection results in the disappearance
o f all but the asphodel.
The dividing line between garrigue and steppe is a narrow one. Generally
steppe is more typical o f recent alluvium spread over arid coastal plains, for
example the Tavoliere di Puglie. All such areas have been over-grazed and the
characteristic vegetation is a discontinuous cover o f tufty grass and halophytes,
the latter most common near the coastal lagoons. In spring this desolation may
be brightened by short-lived grasses and the unprofitable asphodel.
THE SUB-MEDITERRANEAN DECIDUOUS WOODLANDS. Above the evergreen oak
forests (or its degenerate successors), where the siunmers are fresher and the
winters wetter, a stratum composed o f mixed deciduous trees is recognizable.
In central Italy it lies between about 500 and looom and it is best preserved on
the volcanic areas o f the Anti-Apennines. In these woodlands box, ash-elm and
walnut are represented but oaks are the dominant group. They include the two
northern European species as well as those more typically southern (Q. pubescens,
Q. cerris,Q. macedónica). It is climatically significant that towards the upper limit
of this stratum olive cultivation becomes marginal and it is widely replaced in
the economy by the almond and the hazel nut.
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