Hazelnuts are sweet, and incredibly nutritious edible kernels from the “birch” or Betulaceae family of trees. “Filbert” (C.maxima) is similar in kind, and related to the common hazel but only differing in having its nut totally covered by its tubular involucre. In Britain, both of these nuts are in general enjoyed as “cobnuts.”
Hazel tree begins producing fruits about three years after plantation. During each spring season, the tree bears attractive inflorescence (catkins) consisting of clusters of monoecious (single sex) flowers arranged closely along its central stalk which subsequently develop into fruits by autumn.
Hazels appear in clusters. Each nut is held inside the short leafy involucre or “capsule” enclosing about three-quarters of the kernel. Each yellow-brown color kernel is roughly spherical to oval in shape, about 1.5-2 cm long and 1.2 -2 cm broad, featuring a light scar at its base. They generally fall out of this leafy involucre or capsule once ripe about 7-8 months after pollination.
Hazelnut oil, extracted from the kernels, has been used in as base or carrier oil in medicine, and in aromatherapy.
Hazelnuts are eaten on its own, roasted, salted, or sweetened. Hazels as well as filberts are nutty yet pleasantly sweet in taste.