Treks of tiik Xoktukk.v United States 9-'3 



iil)right branches ; hraiichlets pubescent. Leaves rough above, 

 pubescent beneath, doubl)' serrate, often somewhat 3-lobed at 

 the apex. AFany varieties fine for planting. From Europe. 



lit. Planera Gmcl. Phiiicrlrec. 



Trees with aUernate. two-ranked, straight-veined, in- 

 e(|uilateral, serrate leaves and with bark scaling off in plates. 



Trees similar to the elms but with a nut-like fruit and the 

 dowers exj^anding with the leaves. 



1. Planera aquatica (Walt.) Gmel. I'lanertrec. A 

 small tree with nearly glaljrous leaves growing in swamps and 

 on wet banks. Wood compact, soft, weak, light brown. Ind. 

 to Mo.. Ky., N. Car., Fla. and Tex. 



.")i>. Celtis (Tuuni.) L. llackberry. 



Trees or shrubs with 2-rankcd, simple, leaves with two 

 prominent lateral veins from the base and with interruptedly 

 diaphragmed pith with cavities. 



Flowers in the axils of leaves, on short branches; fruit 

 an ovoid or globose drupe. 



1. Leaves sharply serrate ; smooth or scabrous above ; 



twigs glabrous, especially the fruiting ones, or 



pubescent. C. occidcntalis. 

 1. Leaves entire or few-toothed, small. ('. uiississip- 



pifnsis. 



1. Celtis occidentalis L. COmnioii Hackbcrry. .V 

 medium-sized tree with rough bark. Commonly much dis- 

 torted with "witches brooms." Drupe sweet and edible. 

 Self-prunes the fruiting twigs in winter. Wood heavy, hard, 

 strong, quite tough, greenish-white. In dry soil and on flood 

 plains. Quebec to Man., N. Car.. Mo.. Kan. and Okla. 



1. Celtis mississippiensis Bosc. Southern Hackl)ori> 

 .\ medium-sized tree with light gray, rougii bark. Csually 

 in drv soil. \^;i. to 111.. Mo., Kan., Fla., and Tex. 



