HAMAMELIDAE

11 orders
24 families
3400 species

2/3 of species are in order Urticales
1/4 of species are in order Fagales
remaining 9 orders have less than 300 species

This subclass has a large proportion of taxonomically isolated and relictual families

Mostly wind-pollinated

Contains many of common temperate trees, i.e., oaks, elms, walnuts, hickories, birches, sycamore, mulberry, beech

Flowers are highly reduced and often unisexual