The genus Quercus comprises many species of wild trees in Italy.
In many cases the habit is impressive even though there are species
shrubs. The leaves are alternate, sometimes lobed, sometimes toothed
on the same plant can have different forms, for the difference
of juvenile than adult foliage.
The oaks are monoecious plants, or the same plant in both
male and female flowers. The male flowers are grouped in catkins
yellow, the female flowers are green. The fruit is
acorn, a dome formed by the scales surrounding the base of
walnut.
belong to the genus approximately 450 species of hardy plants, leafy
deciduous or evergreen. The first species of oak appeared on
Earth in the Cenozoic period.
History of European oaks
The French scientist Antoine Kremer has shown through the study
genes of the oaks and pollen fossils during the last Ice Age
populations of Quercus were confined to three areas of refuge located
in Spain, Italy and the Balkans and then re-colonize the territory of
European continent. The present area was occupied from 6000
years BP. The comparison of genetic data and palynological data have determined
colonization routes taken by the various lineages.
pads and in particular the Alps are sometimes delayed or diverted Advanced
but the north-south trajectory is rendered permanently visible. In this
rifugiatesi as the oaks in the Iberian Peninsula
have colonized the entire area to the west, and exclusively in the British Isles.
Oaks rifugiatesi in Italy and the Balkans have made progress towards
Eastern Europe and Russia.
palynological analysis revealed a surprising finding regarding
the speed of this progression, on average, the oaks are advanced
of 380 m per year, with the peak numbers of 500 m per year in some
periods.
The oak branch is the symbol of Roman virtue, strength, courage, dignity and perseverance
.
is the famous oak tree beneath which Tasso used to relax and read
during his stay in Rome.
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