ROSE FAMILY 
MOUNTAIN ASH 
Pyrus americana 
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, unequaily pinnate, six to ten 
inches long, with slender, grooved, dark greei 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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