ROSE FAMILY 



MOUNTAIN ASH 



Pyrus 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. Light 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. 



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

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



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-eighth 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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