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AMERICAN MOUNTAIN ASH. 

 Pyrus americana, (Marshall) De Candolle. 



FORM — A small tree rarely exceeding 20 ft. in height with a diameter of 12 inches. A tree 

 14 inches in diameter is reported from Lycoming county. Trunk rather short and the crown 

 narrow and round- topped. 



BARK — Thin, smooth or slightly scaly and grayish. 



TWIGS — Rather stout, smooth, grayish to reddish-brown, covered with conspicuous, pale, 

 oblong lenticels, pith large, brownish, 



BUDS — Alternate, puiplish-red, smooth or slightly hairy on outside but densely hairy on 

 inside; terminal buds large, about i of an inch long, broadly conical, with 2-3 visible bud- 

 scales, sharp-pointed and often curved at apex; lateral buds about I of an inch long, closely 

 appressed, somewhat flattened, with 1-2 visible bud-scales. 



LEAVES — Alternate, compound, 6-10 inches long, with 13-17 sessile leaflets. Leaflets in pairs 

 except terminal one, lanceolate, 2-3 inches long, sharp-pointed at apex, serrate on margin, 

 tapering or rounded at base. Smooth and dark yellowish-green when full grown, turning 

 yellow in autumn. 



LEAF-SCARS — Alternate, rather large, elevated on a projection of the twig, broadly U-shaped, 

 with wavy margin, containing 3-5 bundle-scars. 



FLOWERS — Appear about :^ay Avhen the leaves are fully developed. They are white, perfect, 

 about i of an inch across, arranged in flat cymes 3-4 inches across. 



FRUIT — Arranged in flat-topped clusters, persisting far into winter, berry-like, about the 

 size of a medium-sized cherry, bright red, round or pear-shaped, in winter wrinkled, its flesh 

 strongly acid. 



WOOD — Di£fuse-porou:3; rays indistinct; soft, weak, brownish, close-grained. Weighs about 

 34 lbs. per cubic foot. Not used commercially. 



DISTINGUISHING CHARACTERISTICS— The American Mountain Ash can be distinguished 

 l»y its alternate compound leaves with 13-17 sessile leaflets which are conspicuously toothed. 

 The flat-topped cymes of wliite flowers measuring about 3-4 inches across, and the bright 

 red fruit about the size of a pea and arranged in flat-topped clusters are characteristic. The 

 stout grayish to reddish-brown twig with conspicuous pale lenticels and the purplish-red, sharp 

 pointed, somewhat gummy and usually smooth alternate buds are also characteristic. 



RANGE — Newfoundl.'ind westward to Manitoba and Iowa, southward in the mountains to 

 North Caiolina. 



DISTRIBUTION IN PENNSYLVANIA— Limited to the mountainous region of the State. A 

 line drawn from the western part of Tioga county south to Somerset county and thence north- 

 east to Monroe county will include the general distribution of this species. 



HABITAT — Prefers moist or rocky hillsides. Often found on the border of streams and locally 

 common on rocky hillsides. 



IMPORTANCE OF THE SPECIES — This species is of no commercial importance. It rarely 

 exceeds a height of ft. w;th a diameter -jf 12-15 inches. It is rather attractive and de- 



serves to be planted for ornamental purposes. Its attractive ornamental features are its form, 

 broad cyme-like clusters of white flowers, and its bright red clusters of fruit which ripen 

 in autumn. 



