  corylus maxima, the filbert, is a species of hazel native to southeastern europe and southwestern asia, from the balkans to ordu in turkey.rushforth, k. (1999). trees of britain and europe. collins isbn 0-00-220013-9. it is a deciduous shrub  tall, with stems up to  thick. the leaves are rounded, 5â12&nbsp;cm long by 4â10&nbsp;cm broad, with a coarsely double-serrated margin. the flowers are wind-pollinated catkins produced in late winter; the male (pollen) catkins are pale yellow, 5â10&nbsp;cm long, while the female catkins are bright red and only 1â3&nbsp;mm long. the fruit is a nut produced in clusters of 1â5 together; each nut is 1.5â2.5&nbsp;cm long, fully enclosed in a 3â5&nbsp;cm long, tubular involucre (husk).flora of nw europe: corylus maxima the filbert is similar to the related common hazel, c. avellana, differing in having the nut more fully enclosed by the tubular involucre. this feature is shared by the beaked hazel c. cornuta of north america, and the asian beaked hazel c. sieboldiana of eastern asia. ==uses== thumb|left|corylus maxima 'purpurea' the filbert nut is edible, and is very similar to the hazelnut (cobnut). its main use is as large filler (along with peanuts as small filler) in most containers of mixed nuts. filberts are sometimes grown in orchards for the nuts, but much less often than the common hazel. the purple-leaved cultivar corylus maxima 'purpurea' is a popular ornamental shrub in gardens. ==language== in oregon, "filbert" is used for commercial hazelnuts in general. use in this manner has faded partly due to the efforts of oregon's hazelnut growers to brand their product to better appeal to global markets and avoid confusion.oregon hazelnut marketing board[http://www.oda.state.or.us/information/aq/aqfall99/07.html agriculture quarterly - oregon department of agriculture
Corylus Edible_nuts_and_seeds