It spans from the Santa María Valley in the province of Salta going through the center of the province of Catamarca and La Rioja, center and east of the province of San Juan and Mendoza, center and east of the province of Neuquén, west of the province of La Pampa, center and east of the province of Río Negro up to the northeast of the province of Chubut.

From an ecological point of view and in accordance with the significance (presence and diversity) of the native forest mass in the phytogeographic province of El Monte, the area is classified in two sub-regions:

The Septentrional Mount with precipitations predominantly in the spring season. It spans from the north, the entire mount up to the center of the province of Mendoza.

The Austral Mount with predominantly winter precipitations. This district spans from 24.40° south latitude in Salta until 27.15° in Hualfín, Catamarca.

The Septentrional Mount presents, in proportion to its surface, a very large wooded area, whereas in The Austral Mount only isolated trees or coppices of very few specimens can be found.