Betulaceae: Corylus avellana L.
Source: Magness et al. 1971
The above species is the filbert grown commercially in the U.S. The tree is small, about 15 feet high, spreading and much branched. The leaves are deciduous, roundish oval, serrate, near glabrous above, somewhat pubescent on the lower veins. The nuts are nearly enclosed in a leafy involucre, but the apex is partially exposed. The shell is hard and woody. The kernel is free inside the shell, and separates freely when cracked. The inconspicuous female blossoms are exposed and pollinated in advance of the leafing out of the trees. In addition to cultivated kinds, 3 species of Corylus, namely C. americana Marsh., C. cornuta Marsh, and C. californica (A.DC.) Rose, are native in the U.S., and nuts from them are often harvested locally.
Production in the U.S.: About 9,000 tons in shell. Additional quantities are imported.
Use: Direct eating, confections.
Part of plant constiined: Internal kernels only.