An erect and symmetrical evergreen tree from the Mediterranean region, where it often grows as a companion to Quercus suber, In adverse conditions it remains a shrub, but can attain heights of up to 25 m and can grow as wide as it is high with a broad, oval dense crown. It has a short trunk which may reach or exceed 3 m in girth. It is very tolerant of drought once established and is tolerant of heat, and cold (to about - 12°C). It will grow well even in limestone subsoils and will propagate from acorns or from root suckers.
The acorns are a favourite food of pigs, giving their meat a special flavour. It is considered the best European acorn for human consumption and also the source of an edible oil. Like many of the oaks, it is an alternate bearer, each tree bearing a heavy crop one year, then a lesser load the following year. By planting a grove of these trees the annual yield is fairly constant. One Portuguese tree yielded 1200 litres of acorns in a good season. Every other year it only pro-duced about 240 litres.