Portuguese oak

Q. faginea is a medium-sized deciduous or semi-evergreen tree growing to 20 metres (66 feet) tall, with a trunk up to 80 centimetres (31 inches) in diameter, with grey-brown bark. The tree can live as long as 600 years. The leaves are 4–10 cm (1+1⁄2–4 in) long and 1.2–4 cm broad (rarely to 15 cm long and 5 cm broad), glossy dark green to gray-green above, and variably felted grey-white below; the margins have five to 12 pairs of irregular teeth. Leaf fall is typically in mid- to late winter. The flowers are catkins, produced between March and April, almost always before holm oak, which grows in similar areas. The acorns are oblong-ovoid, 2–2.5 cm long, maturing in 6 months to disperse in September or October. The species commonly develops galls due to gall wasp activity; the galls are brown, 1–2 cm diameter, and have a spongy, cork-like interior. The two subspecies are:

Portuguese oak also hybridises readily with other related oaks such as Algerian oak (Q. canariensis), downy oak (Q. pubescens), and Pyrenean oak (Q. pyrenaica) (producing the hybrids Q. × tlemcenensis, Q. × subpyrenaica and Q. × numantina, respectively) which can make identification difficult. The specific name faginea refers to the superficial resemblance of the leaves to those of the beech (Fagus).

The wood has been used traditionally as firewood and as timber for construction (beams and posts). The acorns, like those of the holm oak or cork oak, are an important food for free-range black Iberian pigs reared for jamón ibérico production. It is also occasionally planted as an ornamental tree.