ACERACEAE 



Silver Maple 

 Acer saccharinum L. 



HABIT. A handsome tree 60-80 feet high and 2-3 feet in 

 diameter (max. 120 by IVi feet); trunk often separating near 

 ground into several upright branches; crown broad and rounded. 



LEAVES. Simple; orbicular; deeply 5-lobed, with the side 

 of the terminal lobe diverging toward the apex; 4-7 inches 

 long; lobe margins sharply toothed; light green above, glabrous; 

 silvery white below; turning pale yellow in autumn. 



FLOWERS. Polygamous; in crowded fascicles; apetalous; 

 red to yellow-green; appearing before the leaves. 



FRUIT. Key with widely divergent wings n/2-2 inches long; 

 greenish; glabrous; one samara often aborted; maturing in late 

 spring and germinating immediately. 



TWIGS. Slender; dark red; lustrous; with fetid odor when 

 bruised. Winter buds: terminal V8-I4 inch long, blunt, dark 

 red, with 2-4 pairs of visible scales with ciliate margins. 



BARK. Smooth and light gray on young stems; on old trunks 

 becoming separated into scaly plates by narrow fissures. 



WOOD. Moderately important; less heavy and hard than 

 sugar maple and used as a substitute for it. 



SILVICAL CHARACTERS. Tolerant; fast-growing; rather 

 short-lived; moist sites; wide-spreading lateral roots; a common 

 ornamental. 



Red Maple 

 Acer rubrum L. 



This species closely resembles silver maple and differs from it 

 in the following characters: 



LEAVES. Palmately 3-lobed (rarely 5-lobed) with short, 

 broad lobes; the sides of the terminal lobe converging toward 

 the apex; 2-6 inches long; lobe margins toothed; glabrous; 

 light green above, paler and glaucous below; turning scarlet 

 in autumn. 



FLOWERS. Petals present; reddish. 



FRUIT. Key with slightly divergent wings V2-I inch long. 



TWIGS. Without fetid odor when bruised. 



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