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ACERACEAE, the Maple Family 



Trees or shrubs, with opposite, lobed or compound leaves and 

 inconspicuous flowers; sepals about 5; petals the same number, or 

 none; stamens 4 12; ovary 2-lobed, ripening into a pair of winged 

 fruits. 



la. Leaves compound (tree; flowers appearing before the leaves) 



Box Elder, Acer neprundo, 

 Ib. Leaves simple (Maple) 2. 



2a. Shrubs or small trees; leaves 3 5-lobed; the lobes with 

 regularly serrate margins (flowers greenish-yellow, appear- 

 ing later than the leaves) 3. 



2b. Trees; leaves 3 7-lobed; margins of the lobes entire or 

 incised, but never regularly -serrate 4. 



3a. Leaves finely and sharply serrate; twigs smooth; bark con- 

 spicuously striped with white lines 



Striped Maple, Acer peimsylyaiiiciim. 



3b. Leaves coarsely and bluntly serrate; young twigs pubescent; bark 

 not striped Mountain Maple, Acer spicatum. 



4a. Angles between the leaf-lobes rounded (flowers greenish- 

 yellow, appearing with the leaves) 5. 



4b. Angles between the leaf-lobes acute or obtuse, but not 

 rounded (flowers purple, red, or yellowish, appearing before 

 the leaves) 6. 



5a. Leaves glabrous beneath, or minutely pubescent on the veins 



Sugar Maple, Acer saccliarum. 

 5b. Leaves downy beneath Black Maple? Acer saccliarum yar. nigrum. 



6a. Middle leaf-lobe usually more than half the length of the 

 leaf, narrowed at its base; broken twigs with a strong odor 



Silver Maple, Acer saccharinum. 



6b. Middle leaf-lobe usually less than half the length of the 

 leaf, its sides parallel cr broadened at the base; broken twigs 

 without strong odor Red Maple, Acer rulmim. 



SAPI1VDACEAE, the Soapberry Family 



Trees, with opposite palmately compound leaves, and showy white 

 or yellowish flowers in panicles in spring '. sepals 5; petals 4 or 5; 

 stamens about 7; fruit a smooth browji nut. 



la. Leaflets 7; buds viscid; corolla of 5 petals 



Horse Chestnut, Aesculus hippocastanum. 

 Ib. Leaflets 5; buds smooth; corolla of 4 petals 



Buckeye, Aesculus glabra. 



