About 40 species in this genus, including evergreen and deciduous shrubs and trees. Bark is generally smooth, purplish-brown and with distinct lenticels, becoming scaly or furrowed on older trees. Leaves alternate, margin entire, wavy, or toothed, 4-22 pairs of veins, number of veins and teeth used in identification. Male and female flowers. Native to southern South America, New Zealand, eastern Australia, and New Guinea. Note: Every four to six years or so Nothofagus produces a heavier crop of fruit ("beech nuts') which fall to the ground in August. This is known as the beech mast. In New Zealand, a heavy beech mast causes an increase in the population of introduced mammals such as mice, rats and stoats. When the rodent population collapses, some begin to prey on native bird species, many of which are threatened with extinction.
Nothofagus: from the Greek nothos, false, and Fagus (Beech). The genus is closely related to Fagus, differing in a many seeded involucre and lack of a true terminal bud.