ROSE FAMILY 



MOUNTAIN ASH 



Pyriis americhna 



A small tree which loves the north and climbs the high mountain 

 ranges of Virginia and North Carolina, but does not cross the Rock- 

 ies. Prefers a rich moist soil and the borders of swamps, but will 

 flourish on rocky hillsides. Attains its largest size on the northern 

 shores of Lakes Huron and Superior ; in the United States it is usu- 

 ally a shrub. 



Bark.—Ught gray, smooth, surface scaly. Branchlets downy at 

 first, later become smooth, brown tinged with red, lenticular, finally 

 they become darker and the papery outer layer becomes easily sep- 

 arable. 



lyood. — Pale brown ; light, soft, close-grained but weak. Sp.gr., 

 0.5451 ; weight of cu. ft., 33.97 lbs. 



Winter Buds. — Dark red, acute, one-fourth to three-quarters of 

 an inch long. Inner scales are very tomentose and enlarge with 

 the growing shoot. 



Leaves. — Alternate, compound, unequally pinnate, six to ten 

 inches long, with slender, grooved, dark green or red petiole. Leaflets 

 thirteen to seventeen, lanceolate or long oval, two to three inches 

 long, one-half to two-thirds broad, unequally wedge-shaped or 

 rounded at base, serrate, acuminate, sessile, the terminal one some- 

 times borne on a stalk half an inch long, feather-veined, midrib 

 prominent beneath, grooved above. They come out of the bud 

 downy, conduplicate ; when full grown are smooth, dark yellow green 

 above and paler beneath. In autumn they turn a clear yellow. 

 Stipules leaf-like, caducous. 



Flowers. — May, June, after the leaves are full grown. Perfect, 

 white, one-eightli of an inch across, borne in flat compound cymes 

 three or four inches across. Bracts and bractlets acute, minute, 

 caducous. 



Calyx. — Urn-shaped, hairy, five-lobed ; lobes, short, acute, im- 

 bricate in bud. 



Corolla. — Petals five, creamy white, orbicular, contracted into 

 short claws, inserted on calyx, imbricate in bud. 



Stamens. — Twenty to thirty, inserted on calyx tube ; filaments 

 thread-like ; anthers introrse, two-celled ; cells opening longi- 

 tudinally. 



Pistil. — Two to three carpels inserted in the bottom of the calyx 

 tube and united into an inferior ovary. Styles two to three ; stig- 

 mas capitate ; ovules two in each celL 



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