Handbook of Trees of the Noktiiern States and Canada. 423 

 WALNUT FAMILY. JUGLANDACE^. 



A family of six genera and about thirty-five species of impoi-tant trees witli aromatic 



barli and \yatery juice, mostly of the warmer parts of the north temperate zone. Two genera 



are represented in the United States. 



Lcai-cs alternate, deciduous, odd-pinnate, with long grooved petioles exstipulate, the 

 leaflets sessile or nearly so excepting the terminal one which is usually long-stalked. Floicers 

 monoecious, opening after the unfolding of the leaves ; the staminate 'in long drooping lateral 

 aments on the growth of the previous season ; calyx 3 to 6-lobed, each in the axil of and 

 adnatc to a bract ; stamens several with short distinct filaments and longitudinally dehiscent 

 anthers ; pistillate in spikes or solitary terminating the new growth, bracteate and usually 

 two-bracteolate ; calyx 3-5-lobed ; ovary inferior and 1-celled or incompletely 3-4-celled and 

 containing a solitary erect orthotropous ovule ; style short with 2 plumose stigmas. Fruit 

 a bony incompletely 2-4-celled nut inclosed in an indehiscent or 4-valved exocarp ; seed without 

 albumen, large, solitary, 2-lobed, fleshy and very oily ; cotyledons 2-lobed, corrugated or 

 sinuose ; radicle minute, superior, at apex of nut. 



KEY TO THE GENERA. 



Husk of fruit indehiscent ; nut mostly .sculptured ; staminate aments simple ; pith segmented. 



Juglans. 

 Husk 4-valved ; nut not sculptured ; staminate aments branched ; pith not segmented, 



Hicoria, 



THE WALNUTS AND BUTTERNUTS. Genus JUGLANS L. 



Trees with dark colored durable heart-wood, furrowed bark, stout branchlets, laminated 

 pith and edible nuts. Ten species are known, four of which are natives of the T'nited States, 

 two of the northern Atlantic states, one of the southwestern states and one of the I'acific 

 coast region. 



Leaves with stout pubescent petioles and 11-17 subsessile. oblong-lanceolate leaflets which 

 are mostly from 2 to 4 inches long, rounded and unequal at base, finely serrate except at base, 

 acute or acuminate and clammy pubescent at least when young, rugose above ; leaf-buds 

 superposed. Floirerx staminate in thick drooping cylindrical aments 3-.5 in. long or more; 

 calyx usually O-lobed, light yellowish green, puberulous outside ; stamens 8-40 with nearly 

 sessile dark brown anthers ; pistillate flowers in few-flowered siiikes at the ends of the 

 shoots of the season with villous laciniated involucre ; calyx 4-lobed ; petals 4, alternate 

 with the sepals and adnate to the ovary ; pistil with very short style ; two plumose stigmas 

 and usually 2-celled ovary. Fruit globose or ovoid with fibrous somewhat fleshy indehiscent 

 exocarp and an ovoid or flattened globose hard thick-walled rugose or sculptured indehiscent 

 endocarp (nut) which is 2-4-celled at base; seed deeply lobed. 



The name is of Latin derivation meaning nut of Jove. 



KEY TO THE SPECIES. 



Fruit subglobose, papillose (not viscid) ; leaflets 15-23 J. nigra. 



Fruit pointed-ovoid, viscid-pubescent; leaflets 11-17, viscid-pubescent J. cinerea. 



For species see pp. J/S-Sl. 



THE HICKORIES. Genus HICORIA Raf. 



The Hickories are confined to the temperate regions of eastern North America ranging 



from the valley of the St. Lawrence River to the highlands of Mexico. There are about 



a dozen species, all being found within the United States excepting one. Their wood is very 



strong, flexible and more valuable than any other woods for certain uses. They have smooth 



gray bark when young, but with age become fissured into hard plates and scales. The branches 



are tough and flexible and the pith solid. 



Leaves with thick and firm ovate to obovate leaflets, increasing in size from l)elow up- 

 wards, often glandular-dotted, usually unequal at base, and acuminate at apex, serrate, veins 

 commonly forking near the margins. Flowers: staminate aments slender, drooping and 

 usually in threes with common peduncle from the axils of leaf-scars at the base of the shoots 

 of the season or in clusters from buds in the axils of leaf-scars near the summit of the 

 growth of the previous season, the lateral branches from the axils of persistent bracts; 

 calyx 2-3-lobed, adnate to the bracts ; stamens 3-10 with ovate-oblong hairy anthers ; pistillate 

 flowers sessile, in mostly 2-10-flowered terminal spikes ; calyx unequally 4-lobed ; stigmas 

 short-papillose. Fruit subglobose, oblong, ovoid or pyriform, with husk (epicarp) woody at 

 maturity and separating more or less completely into 4 valves, the sutures alternate with 



