Hoyt Arboretum, Portland, Oregon, USA

Family: Fagaceae

Distribution: Texas

Comments: Monterrey oak is a medium-sized semi-evergreen North American native tree to 40’ feet tall and a broad, rounded crown. Naturally occurring only in one known U.S. population, near the Devil's River in Val Verde county, but more common in Mexico. Now planted widely as a landscape tree. Leaves are thick, leathery, and semi-evergreen, with distinct raised veins on the yellowish underside. Simple, alternate, 2" to 5" long, highly variable, but often with several shallow lobes or teeth towards the tip. New leaves in spring are peach-colored and in colder climates the leaves are late-deciduous and turn yellow-brown. Male and female flowers borne in spring on the same tree, the male flowers on catkins up to 4" long, the female flowers less conspicuous. Acorn matures in one year, up to 1" long and enclosed one-half by the acorn cup. Dark to light gray bark, developing scales and flaky plates, then shallow fissures on older trunks. It is widespread in Mexico, Guatemala, and Honduras, only recently discovered in the U.S. (1992) as a native tree species, but widely available in commercial nurseries.