The transition from the Mediterranean to the submontane area is marked by the prevalence of deciduous trees represented by oak woods of the English type and even more by varieties and breeds belonging to Q. downy , and to Q. cerris , from the chestnut groves in the siliceous soils, while in propitious exposures and where the rainfall is accentuated there is the same beech that once lowered even more and even at lower altitudes there is the emblem of the moor, the Calluna which, to quote just one example, forms the undergrowth of the land slope of the Portofino promontory covered with deciduous trees, while the slopes overlooking the sea have the maritime pine, the Erica arborea, cysts, holm oaks and many other types of the ever-growing scrub and wood: indeed it is a characteristic of the area to host elements of the two consortiums, now in continuity with the coastal formations, now in islands where the conditions are partially propitious: the holm oaks reach 1000-1200 m. intersecting with the beech or with this one pushing up to the top of the kiss-shaped side : in the southern Apennines the Q. farnetto acquires importance in this area: in Sicily, the Q. cerris forms a band between 700 and 1000 m., more rarely at 1500 m., and which overlaps the cork groves, but there is an intersection area where magnificent specimens of Q. pseudo– suber conceived as a product of crossing between the two essences: the alder of Naples ( Alnus cordata Ten.) Widespread in the southern Apennines which has its counterpart in A are two elements with an oriental affinity . sub- stringed Mey. of the Caucasus and a local form of Platanus orientalis in some valleys of Basilicata and Calabria and, even more abundant, in eastern Sicily. An area, therefore, of tension and contrast whose vegetation perhaps reflects better than others those climatic oscillations that characterized the Quaternary and the immediate postglacial period and the modifying work of man, as will be better described later. Apart from the altitude, it can be assimilated to the Po Valley area with the annexed hilly districts and the moraine systems: the mixed oak woods, the moorlands of the diluvial plateaus where the Calluna dominates , the chestnut woods, the islands of Mediterranean scrub in the Euganean, the microthermal colonies where peat bogs emerge, the steppe offshoots in the more clastic substrates of the recent moraine, while the ancient one has the Mediterranean Erica arborea, are so many elements of contrast which is, as we said, almost a prerogative of this area. It is easy to recognize its signs and exponents in the more or less wide foothills of the Alps and around the lake basins with the chestnut groves of the insubric sector, the patches of cistus salviefolio and arboreal heather in the solatii of Lake Como, the laureti of the Brescia side of the Garda and almost everywhere the mixed wood of Quercus lanuginosa and Q. ilex which also covers the slopes of the lower Sarca valley up to the Toblino basin and up to about 1000 m. where the holm oak reaches, with the olive tree stopping a little further down, one of the highest latitudes and another of its colony is in the Gorizia basin, well known for its temperate winter climate: very extensive and completely isolated is the colony of Erica arborea in the middle valley of the Chiese between Caffaro and Brione where, with Calluna and Sarothamnus , it forms the undergrowth of extensive chestnut groves. These facts lead to the conclusion that the Mediterranean region with its expansions reaches the extreme limits of the submontane zone and it is these radiations that are one of the causes of that mosaic of consortia that characterize it.
According to remzfamily, the mountain area is properly the climate of beech and high mountain conifers. The Alps have the former in common with all the Apennines, Sicily and Corsica (see alps; Apennines): beech woods now pure, but more often associated with silver fir ( Abies alba ) which has similar ecological needs to beech in the Alps , with the spruce ( Picea excelsa ) capable of resisting a more rigid and continental climate and which therefore ends up overlapping it, in Calabria and on Etna with the Laricio Pinus while it is juxtaposed to this in the high mountains of Corsica preferring the pine i sunnier slopes. Other consortiums are Pinus silvestris, which prefers loose and dry soils where it forms even pure pine forests and which serves as a connection with the previous area, apparently also finding itself in the northern Apennines and Corsica, and the same larch ( Larix europaea ), the only deciduous among the homegrown conifers, which moreover form pure and compact larch woods dominated by isolated individuals with almost columnar contracted branches that advance into the subalpine zone, as does the congener L. sibirica that goes beyond the edge of the Siberian forest, into the frozen ground of the tundra. Heliophilus and, therefore, preferably in the sunny exposures, it is replaced in the kissing ones by the Swiss stone pine ( P. cembra) which also tends to occupy the highest positions reaching 2500 m. and with even more isolated individuals: stone pine, larch and picea are Siberian elements missing in the Apennines and in the islands. All the conifers mentioned tend to take the predominance and end up replacing the beech, a basically oceanic essence, as one penetrates the heart of the chain from the Prealps and the more peripheral valleys or enters valleys with little rainfall such as, e.g., the middle and upper part of the Val Venosta, where the sector below the fir forests of the sunny side and the more or less extended edges of the kissing one are covered by a formation with a physiognomy and a steppe structure in which the Pinus silvestris is reduced with small nuclei and Quercus lanuginosa itselfhe is uncomfortable and ends up almost completely disappearing from Castelbello upwards. It is replaced by a sparse bush of juniperus communis , Berberis vulgaris , Hippophaë rhamnoides with interposed cenosis based on Andropogon ischaemum , Stipa capillata (more rare and small colonies St. pennata ) , Lasiagrostis calamagrostis in landslides and cliffs, etc. : very abundant and widespread everywhere some Astragalus and Oxytropis of the steppe type ( A. excapus , onobrychis , leucanthus; Oxytr . velutina , pilosa , etc.), the Telephium Imperati which is also found in the xerothermic colonies of the Val di Susa and Val d’Aosta, etc. On the opposite side the coniferous woods are bordered by a more or less thick belt of Betula alba ( verrucosa ) and in general it is noted in those districts where this plant and the green alder ( Alnus viridis ) become abundant, the beech is scarce or totally missing. It must be borne in mind that the birch has its own endemic breed in the high wooded area of Etna and the alder finds its counterpart in A. suaveolens Req. which surrounds the major elevations of Sardinia and Corsica between 1600 and 1900 m. and it must necessarily be concluded that such links between such distant chains depend on some general distributive factor which will be mentioned later. The forest formations of the mountain area of the Alps have a fundamentally central-European character and this is maintained in the northern Apennines, while in the central the presence of P. nigra , in the southern one this same and P. brutia and P. _ leucodermis which are all Balkan elements and that of P. larch that Calabria has in common with Sicily and Corsica and that goes as far as Spain give these associations a southern imprint with a particularly oriental color; and this demonstrates that the trans-Adriatic affinities are not limited to the coastal zone, nor do they concern only the wood species. A work by A. Trotter on the Balkan elements in Italy in relation to the cavity which was called Adria reveals how conspicuous is the contribution of herbaceous plants of Illyrian origin in the central and southern Apennines.
