It is customary to distinguish three successive zones in the Chilean flora, proceeding from north to south: 1. northern or desert, 2. central temperate – dry or transitional, 3. southern temperate – humid and forest.
The northern district consists, for the most part, of the Atacama desert, one of the poorest regions of vegetation known; the species surveyed barely reach the number of 414 and are all marked by the greatest xerophilia. Composite characteristics of the genera Pluchea and Baccharis, several Teucrium sassicoli, also low trees such as Prosopis siliquastrum and Gourliaea chilensis are Composite characteristics.. The vast sterile expanse of the Atacama excludes the ease of mixing between the Peruvian flora and the Chilean flora, while the particular configuration of the stretch of the Andes (see) corresponding to this district, facilitates the exchanges between the flora of northern Chile and that of the Argentine Pampas, due to the similar climate on both sides and the lack of a high ridge that represents an insurmountable obstacle for exchanges.
Even in the intermediate Chilean area the landscape is generally xerophilic and trees are rare. Instead in middle Chile, as indeed also in the Pampas, on the opposite side of the Andes, the influence of the clayey soil, brownish red, formed by the disintegration of the volcanic rocks, which, drying up and hardening during the dry season, becomes a substratum that is not very favorable to the development of arboreal vegetation. For Chile 2000, please check neovideogames.com.
In fact, the scarce trees remain low and twisted (Acacia cavenia), or are located along the waterways (Peumus boldus, Quillaia Kageneckia, a Jubaea spectabilis palm and a Chusquaea bamboo). Even the particularly arid stations have their own characteristic forms: steppe formations of Graminaceae (Avenee, Poee, Stipee) cover the dry slopes, scattered with bulbous species of the Conanteree group, intermediate between the Liliaceae and the Amaryllidaceae, of herbaceous and suffruttic plants, aromatic for strong production of essential oils, of some xerophilous orchids (Chloraea), and interspersed with more showy species, such as a characteristic Bromeliad (Puya chilensis), some Opuntiaeus (Cereus quisco, Echinocactus, Mamillaria), or by shrubs with green branches at all defoliated and thorny, such as a characteristic Ramnacea (Colletia), which forms vast thickets locally indicated with the name of espinales.
The flora of the middle Chilean region, amounting to over 2500 species, is distinguished by its marked endemism (1800 species with 35 genera, almost all monotypic and especially belonging to the two families of the Composite and the Liliaceae). Equally remarkable are some genera which, although possessing a larger area than that of the Chilean flora and sometimes very vast, nevertheless present numerous local species; so in the Leguminosae Ademia (69), Astragalus (27), Phaca (26), in the Composite Senecio (93), Baccharis (31), Haplopappus (30), Mutisia (23), in the scrofulariacee Calceolaria (31), in the Liliacee Alstroemeria (20), in Verbenaceae Varbena (27), in Borraginaceae Eritrichium (21), etc.
With a clear transition, the cleared landscape of middle Chile passes to the forest of southern Chile or Valdivian forest, which extends from the latitude of Concepción to that of Chiloé; very dense formation, also unassailable by fire.
Epiphytes are scarce, but the very numerous lianas (Luzuriaga, Lapageria, Cornidia) inextricably bind the trunks together, while the free spaces are filled with thick bamboo reeds (Chusquaea) or occupied by the immense leaves of the Gunnera scabra.
The bottom of the arboreal vegetation is constituted by several species of southern beech, Notophagus with persistent leaves or even deciduous (F. Betuloides, dombeyi, oblique) between them and the oblique Fagus replaces almost completely in Chile on F. Antarctic, which in turn dominates the part of this formation that continues in Tierra del Fuego; followed by several Lauraceae (Persea), the characteristic Magnoliacea of the southern Andes (Drymis Winteri), a Mirtacea (Luma), a Euphorbiacea (Aextoxicon). Particularly interesting from a geographical point of view, are the species that find their representative forms in the Pacific archipelagos or even on the opposite shores of the ocean. Such an arborescent Composite (Flotowia) connecting southern Chile with Juan Fernández and the Galápagos, some Proteacee (Embothrium, Lomatia, Guevinia) reminiscent of Australia, and numerous other genera, such as, to mention only tree plants, the already mentioned Antarctic beeches, Aristotelia (Tiliacee), Encryphia (Rosaceae), Peumus, Laurelia (Monimiacee), Caldcluvia (Saxifragaceae), recalling congenital or repeated types in Australia, Tasmania, New Zealand. Probable continental relations, but certainly interrupted by very remote periods, also recall some disjoint genera of Conifers; so are the genera Araucaria, which reappears with two species in New Caledonia, one on the island of Norfolk and one in Australia; Libocedrus with one species in California and one in New Zealand; Fitzroya with two species in southern Chile.
As is known, the forest area of the Valdivian region extends upwards until it almost reaches the limit of permanent snow (1462 m), abandoning a relatively narrow strip of orophilic vegetation consisting of twisted shrubs and a rich mix of herbaceous species. In the middle Chilean area, on the other hand, the snowline, due to the dryness of the climate, rises to over 4400 meters above sea level, so that the area offered for the expansion of orophytes would be exceptionally large, if the Andean chain were not reduced. here to a simple, relatively very narrow mountain range. Characteristic of this area is the mixture of orophilic species of the northern hemisphere (Ranuncolacee, and genera Alsine, Saxifraga, Alchemilla, Gentiana) with Antarctic species (Graminaceae of the genera Poa and Hierochloa and the genera Azorella, Acaena, Pernettya, etc.).