Broadleaf, evergreen tree or shrub, commonly grows to about 40 ft (12 m) tall, and may be a multi-stemmed shrub; occasionally a tree will attain a height of 65 ft (20 m). Leaves are alternate, compound (pinnate or bipinnate), 20-42 cm long and 12-30 cm wide, 3-30 leaflets per leaf, each 16 × 7 cm, ovate-elliptic, surface rich, glossy green, margin coarsely toothed. Inflorescence is a bottle-brush spike carrying bisexual, white flowers, each to 2.5 cm, and followed with cherry-red, spherical fruit, about 1.2-2.3 cm, which mature brown or black and contain a single edible seed.
- Filtered sun or partial shade, well-drained soil, regular water (don't over water)
- Hardy to USDA Zone 9 (25°-20° F), but it appeares to be somewhat hardier, for it is growing in Washington Park Arboretum in Seattle, Zone 8b (15-20° F). Reportedly when dorment may survive temperatures to 14° F (-10° C), new spring growth is sensitive to frosts.
Seeds are eaten raw or cooked, have a pleasant taste, are similar to filberts/hazelnuts, although they are not related. The origin of the Spanish common name, avellano, comes from the fact the Spanish settlers found the nuts similar to the hazelnuts (Corylus avellana) they knew from Europe.