ARONIA 109 



ARONIA Medic. (Rosaceae) 



Deciduous shrubs. Twigs moderate, rounded, glabrous; pith 

 moderate, rounded, continuous. Buds solitary, sessile, oblong, 

 flattened, appressed. Leaf-scars alternate, crescent- shaped or 

 U-shaped; bundle-traces 3; stipule-scars none. 



a. Twigs and buds somewhat 



woolly 1. A. arbutifolia 



a. Twigs and buds glabrous 2. A. melanocarpa 



1. A. arbutifolia (L. ) Ell. Red Chokeberry . ( Pyrus arbuti - 

 folia (L. ) L.f,). A shrub 1-2. 5 m. high; twigs and buds more or 

 less wooUy;leaf-scars low; bundle-traces 3; fruits red, persistent 

 into winter. Swamps and damp barrens, Ontario to Michigan and 

 Missouri, south to Florida and Texas (Fig. 134). 



2. A. melanocarpa (Michx. ) Ell. Black Chokeberry . ( Pyrus 

 melanocarpa (Michx. ) Willd. ) A shrub up to 4 m. high, but gen- 

 erally considerably lower; twigs and buds glabrous; leaf-scars 

 low; bundle-traces 3; fruits black, persistent into winter. Moist 

 thickets and barrens, Newfoundland to Minnesota, south to South 

 Carolina and Tennessee (Fig. 135). 



SORBUS L. (Rosaceae) 



Erect-branched small or moderate deciduous trees. Twigs 

 moderate, with prominent lenticels, rounded; pith round, brown, 

 continuous. Buds oblong, the terminal large, the lateral reduced, 

 solitary, sessile, more or less pubescent with long hairs matted 

 in gum. Leaf-scars alternate, raised, crescent-shaped or linear; 

 bundle-traces 3 or 5; stipule-scars none. 



1. S. am eric ana Marsh. Mountain- Ash . ( Pyrus americana 

 (Marsh. ) DC. ). A tree 6-10 m. tall, 2-3 dm. in diameter; twigs 

 rather thick, with prominent lenticels; buds oblong, the terminal 

 large, the lateral smaller, solitary, sessile, more or less pubes- 

 cent with long hairs matted in gum; leaf-scars raised, crescent- 

 shaped or linear; bundle-traces 3 or 5; fruits orange-red, 4-6 

 mm. in diameter, holding through the winter, but fading. Woods, 

 Newfoundland to Minnesota, south to Georgia and Illinois (Fig. 136). 



AMELANCHIER Medic. (Rosaceae) 



Deciduous trees or shrubs. Twigs rather slender, zigzag, 

 terete; pith more or less 5-angled, continuous, pale. Buds mod- 

 erate, sessile, solitary, elongated, with about 6 often twisted 



