Diversity:  7 genera and about 60 species of deciduous trees

Distribution:  North temperate with southern extensions into both Old and New World subtropics at higher elevations - 2 genera with 12 species in Texas.

Floral structure:

Significant features:  Common and important elements of North temperate deciduous forests world wide, including Walnut (Juglans) and Hickory (Carya) species.  Distinctive by their 'amentiferous' floral structures combined with alternate, pinnately compound leaves that are often aromatic and a distinctive fruiting structure.  The true fruit is a nut, but this is enclosed in an indehiscent, leathery or fibrous 'husk' derived from the involucre.  The mature seed contains a fully developed embryo (convoluted or contorted contents of a walnut or pecan represent its cotyledons.  Thus, a high protein/oil food product for both wildlife (ecological importance) and humans (economic importance - English walnut = Juglans regia and pecan = Carya illinoensis).
 

Carya texensis - staminate inflorescence at anthesis

Carya texensis - pistillate inflorescence at anthesis

Juglans regia - overview from Kohler's Medicinal Plants
 

More information on the Juglandaceae