The Clays and the Gullies

The hill territory to the South of Castel San Pietro Terme is undulated in the first hills and then it becomes varied in height next to the first mountains.
The first hills are the place of many ancient settlements, of specialised agriculture, above all with grapevine cultivation. They are characterised by slight slopes which alternate with steep ones.
In the shady valleys there are remains of the ancient woods, with oaks, ash trees and horn-beams.
Going on towards the mountains you reach Pleistocene and Pliocene clayey grounds, which are the marine deposits dating back to 5 million years ago. Those in Castel San Pietro Terme territory are the last offshoots of Pliocene clays in low-level calm sea. These hills are not very high, almost devoid of arboreal vegetation, with wide gully areas, which have the shape of evocative crests and offsets.
These are lands rich in perfectly preserved fossils.
The slopes of gullies lack in vegetation because the high concentration of minerals in the ground allows only some species to survive, similar to those living in the coastal habitat.
To the South of Pliocene clays starts the "scaly clays" formation, which extends in the whole remaining area of the Municipality. One of the most interesting natural features of scaly clays is that they are rich in minerals being grounds composed of many types of rocks.
This formation characterises most part of the Apennine Mountains and it ends, in our region, slightly to the East of Sillaro valley. These grounds are mainly composed of grey-greenish clays containing rock fragments of different dimensions and ages (from 160 to 22 million years) and of different origin: sedimentary, magmatic, etc.
Also scaly clays morphology is characterised by gullies, of a less steep shape than Pliocene clays; moreover, because of the lower concentration of salt in it, the flora is more varied. The moon-shaped landscape of gully areas has its own particular charm. Then, in less steep areas, in spring and at the beginning of summer, among the green of junipers, breaks out the yellow of brooms, the white of hawthorns and of wild roses, the flashing red of sulla.
The low presence of humans in that area because of its weak fertility, generally allow the maintenance of a quite free and undisturbed natural habitat.
Finally, there is Montecalderaro group, 600 metres in altitude, whose environmental features are completely different from scaly clays. In the highest part the traditional chestnut grove environment has an overlooking presence. Where there are not chestnut trees, the wood is composed of sessile oaks, elm trees, ash trees, maple trees, black horn-beams, wild cherry trees, cornel trees, laburnums, elders. For an overall view of that area you can go on into the carriage road from Montecalderaro to Sillaro valley, passing near the ancient attractive Borgo di Frassineto.