20 



AMERICAN MEDICINAL BARKS. 



The price paid for white oak bark ranges from 1 to 3 cents a pound. 

 The bark is a powerful astringent and is also antiseptic. 



SLIPPERY ELM. 



Ulmus pubescens Walt. 



Pha rm a cop oeia I na m e. — Ulmus. 

 Synonym. — Ulmus fulva Michx.° 



Other common names. — Moose-elm, red elm, Indian elm, rock-elm, sweet 

 elm. 



Habitat and range. — This tree is native in woods, along streams, and on hills 

 from Quebec to North Dakota, south to Florida and Texas. It is more common 

 in the western part of its range. 



Description of free.— The slippery elm is usually about 40 to 50 feet in height, 

 although it will sometimes grow as tall as TO feet, with a trunk about 2* feet 



in thickness. In dense woods it grows 



tall and straight, branching some dis- 

 tance from the ground, but in open 

 woods and fields, where it often occurs 

 singly, it is more spreading and ir- 

 regular in growth. It has a dark, red- 

 dish wood, hard and durable, and is 

 covered .with a rough, reddish brown 

 bark (fig. 13). Even the small 

 branches are rough and the twigs are 

 furnished with rough hairs. The leaf 

 buds, a few weeks before expanding, 

 are soft and downy with rust-colored 

 hairs. Short downy stalks support the 

 rather large leaves, the upper surface 

 of which is very rough and the lower 

 hairy. The leaves are about 4 to 8 

 inches long and about 2 to 1\ inches 

 wide, pointed at the apex, usually 

 lance-shaped oval in outline, sharply 

 toothed, and with an obtuse, unevenly 

 shaped and generally heart-shaped base. 

 The flowers appear very early in the spring (in March or April), before the 

 leaves. They occur in dense, lateral clusters and consist of a bell-shaped, downy 

 calyx, usually 7 lobed, no corolla, and 5 or 7 reddish stamens. The winged fruit 

 which follows, known boranieally as a " samara," is flattened and circular ; 

 the seed is borne in the center, surrounded by the winged, membranous margin, 

 which aids its dispersion by the wind (fig. 14). Slippery elm belongs to the 

 elm family (Ulmacese). 



Description of bark. — The commercial article consists of pale brown or whitish 

 brown fiat pieces tied in bundles, and it also occurs on the market in smaller 

 pieces of uneven size, suitable for grinding purposes, but which bring a lower 

 price. The flat pieces are of varying length and width, about an eighth of an 



Fig. 13.— Slipp 



•y elm (Ulmus pubescens), 

 trunk. 



a The pharinacopoeial usage. 



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