Nothofagus

Nothofagus, commonly known as southern beech, is a genus of woody plants in the family Nothofagaceae. It comprises roughly 40 to 50 species of trees and shrubs native to temperate regions of the Southern Hemisphere. The genus has a predominantly Gondwanan distribution, with species occurring in southern South America (Chile and Argentina), New Zealand, Australia (Tasmania and parts of the mainland), and, in some classifications, New Caledonia. Nothofagus plants are important components of temperate forests and contribute to regional biodiversity and forest structure.

Leaves are typically simple and arranged alternately; they are often evergreen, though some species are deciduous in cooler climates. Flowers are inconspicuous, and the fruit is a small woody capsule containing one or more seeds. Seed dispersal is mostly local, through gravity, with occasional wind aid in some species. Growth forms range from shrubs to tall trees, and lifespans can be long in favorable conditions.

Nothofagus has a long fossil record dating back to the Late Cretaceous, supporting its role in the historical assembly and breakup of the Gondwanan flora and explaining its current disjunct distribution across southern continents. Taxonomic treatment varies, but the genus is generally recognized as comprising multiple evolutionary lineages or subgroups.

Ecologically, Nothofagus species commonly form dominant canopies or subcanopies in temperate forests and interact with soil microbes in mutualistic associations. They are cultivated for timber, ornamental use, and reforestation in suitable climates. Some populations face threats from habitat loss, disease, and other ecological pressures, prompting regional conservation efforts.