Corylus maxima aka Filbert

Corylus maxima, commonly known as the filbert, is a deciduous shrub native to southeastern Europe and southwestern Asia. It belongs to the birch family Betulaceae and can reach a height of 6–10 meters with thick stems. The leaves are rounded with a coarsely double-serrated margin, measuring 5–12 cm long by 4–10 cm broad. In late winter, wind-pollinated catkins appear, with the male catkins being pale yellow and 5–10 cm long, and the female catkins being bright red and only 1–3 mm long. Clusters of nuts, enclosed in a tubular involucre (husk) that is 3–5 cm long, are produced. The filbert is similar to the common hazel but has a more fully enclosed nut. It is also similar to the beaked hazel found in North America and eastern Asia. The filbert nut is edible and used in mixed nuts, while some cultivars are grown for ornamental purposes. In Oregon, "filbert" is used to refer to commercial hazelnuts.