The Elms and the Hackberries 



3. Genus PLANERA, Gmel. 



Water-loving trees of small size. Leaves elm-like, small, 

 unsymmetrical. Flowers polygamo-monoecious, axillary, small. 

 Fruit a dry drupe in crustaceous husk. {P. aquaiica) planer tree 



I. Genus Ulmus, Linn. 



The genus Ulmus has sixteen known species, distributed in 

 all north temperate countries except western North America. 

 Five species are native to our Eastern States and one to the 

 Southwest; Europe has three, two of which extend to eastern 

 Asia and northern Africa. Southern and central Asia have 

 representatives. Elms are valuable timber trees, and have 

 always been planted for shade and ornament. Many varieties 

 have arisen in cultivation among the European species. So far 

 the American species have, shown few horticultural forms. The 

 elms are distinguished by their simple, unsymmetrical, 2-ranked 

 leaves, and their thin, circular, winged samaras. Their wood 

 is tough, heavy and hard, with interlacing fibres which make it 

 difficult to split. 



White Elm, American Elm (Ulmus Americana, Linn.) — 

 A tall, graceful, wide-spreading tree, 75 to 125 feet high, usually 

 of symmetrical, vase shape, with slender limbs and pendulous 

 twigs. Bark dark or light grey, rough, coarsely ridged ; branches 

 grey; twigs reddish brown. Wood reddish brown, with pale 

 sap wood; coarse, hard, heavy, strong, cross grained, difficult to 

 split, durable in water and soil. Buds acute, flattened, smooth; 

 flower buds lateral, large. Leaves alternate, 2 to 6 inches long, 

 obovate, doubly serrate, acuminate, unequal at base; smopth 

 above when mature; ribs parallel. Flowers, March, before leaves, 

 on slender, drooping pedicels in umbel-like clusters, perfect, 

 greenish red, inconspicuous. Fruit, May, sm.ooth, oval with thin 

 ciliated circular wing, notched above to the nutlet. Preferred 

 habitat, rich, moist soil. Distribution, Newfoundland to Florida; 

 west to Rocky Mountains. Uses: Favourite shade and orna- 

 mental tree. Wood used for hubs, saddle trees, barrels and kegs, 

 flooring, in boat and shipbuilding, flumes and piles. Indians used 

 bark for canoes and ropes. 



Up and down New England the trolley cars ply in a maze 

 230 



