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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 May when the leaves are fully developed. They are white, perfect, 

 about i of an inch across, arranged in flat cymes 8-4 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 Diffuse-porous; rays indistinct; soft, weak, brownish, close-grained. Weighs about 

 34 Ibs. per cubic foot. Not used commercially. 



DISTINGUISHING CHARACTERISTICS The American Mountain Ash can be distinguished 

 ly its alternate compound leaves with 13-17 sessile leaflets which are conspicuously toothed. 

 The flat-topped cymea of white 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 reddibh-brown twig with conspicuous pale lenticels and the purplish-red, sharp 

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



RANGE Newfoundland westward to Manitoba and Iowa, southward in the mountains to 

 North Carolina. 



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 2C-S.P ft. with a diameter ->f 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. 



