RUTACEiE— RUE FAMILY 



WAFER ASH. HOP-TREE 



Ptilea trifolihta. 



Ptelea, of Greek derivation, is the classical name of the elm 

 tree, which was transferred by Linnaeus to this genus, because 

 of the resemblance of its fruit to that of the elm. Trifoliata re- 

 fers to the three-parted compound leaf. 



A small tree, sometimes reaching the height of twenty feet, often 

 a shrub of a few spreading stems. It makes part of the under- 

 growth of the forests of the Mississippi valley, and is found most 

 frequently on rocky slopes. Has thick fleshy roots, flourishes in 

 rich, rather moist soil. Its juices are acrid and bitter and the bark 

 possesses tonic properties. 



Bark. — -Dark reddish brown, smooth. Branchlets dark reddish 

 brown, shining, covered with small excrescences. Bitter and ill- 

 scented. 



Wood. — Yellow brown ; heavy, hard, close-grained, satiny. Sp. 

 gr., o. 83 1 9 ; weight of cu . ft. , 5 1 . 84 lbs. 



Whiter Btids. — Small, depressed, round, pale, covered with sil- 

 very hairs. 



Leaves. — Alternate, compound, three - parted, dotted with oil 

 glands. Leaflets sessile, ovate or oblong, three to five inches long, 

 by two to three broad, pointed at base, entire or serrate, gradually 

 pointed at apex. Feather-veined, midrib and primary veins prom- 

 inent. They come out of the bud conduplicate, very downy, when 

 full grown are dark green, shining above, paler green beneath. In 

 autumn they turn a rusty yellow. Petioles stout, two and a half to 

 three inches long, base enlarged. Stipules wanting. 



Flowers. — May, June. Polygamo - monoecious, greenish white. 

 Fertile and sterile flowers produced together in terminal, spreading, 

 compound cymes ; the sterile being usually fewer, and falling after 

 the anther cells mature. Pedicels downy. 



Calyx. — Four or five-parted, downy, imbricate in the bud. 



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