Hazelnut / Filbert

Hazelnut species are found in cool temperate climates through most of the northern hemisphere and all produce edible nuts but only the ones listed above are in significant commercial production, having much larger nuts than other species. C. avellana is native to almost all of Europe and deep into western Asia. It has been widely introduced in North America. C. maxima is native to southeastern Europe and northern Anatolia. What's the difference? The leafy cover of filberts is much longer than the nut, tighter around the nut, and is reddish in color. The largest producer of hazelnuts, by far, is Turkey, mostly from Ordu on the northern coast. Italy is a distant second. The largest U.S. producer is Oregon state, but recent large plantings in California are coming on-line.

C. hetrophylla is native to central and northern China, southeastern Siberia, Korea and Japan. It is closely related to C. avellana and produces very similar nuts.

The photo specimens of C. avellana include shelled nuts (front), nuts in shell (middle) and nuts still in the leafy husks (involucres). Those in the husks are a rather elongated variety compared to the other shelled specimens and were probably grown in California.

More on Nut Trees.

Hazelnuts can be eaten raw or roasted. Roasted ones are featured in most cocktail nut mixes, along with peanuts, cashews, and possibly Brazil nuts (none of which are nuts, technically). In addition, Hazelnuts are often included as a flavoring thickener in the cuisines of their native regions.