KEY TO THE PRINCIPAL TREE FAMILIES. 



A. The Evergreens, or Conifers, 

 B. Fruit, a cone. 



C. Foliage needle-like, conspicuous, spirally arranged. 

 D. Arrangement of leaves, few in sheathed bundle. 



The Pines 

 DD. Arrangement of leaves, many in unsheathed 



tufts, deciduous The Larches 



DDD. Arrangement of leaves, solitary and scattered. 

 E. Leaves flat, blunt, pale beneath, 2-ranked 

 on twig. 

 F. Cones erect, large; branches stiff; bark 

 smooth, with resin blisters. The Firs 

 FF. Cones pendant, small ; branches sup- 

 ple ; bark rough ; leaves on minute 

 stalks. The Hemlocks 



EE. Leaves 4-sided, sharp at tip, not pale be- 

 neath; standing out in all directions. 



The Spruces 

 CC. Foliage scale-like, minute, 4-ranked, close pressed 



to twig; cones small. The White Cedars 



BB. Fruit, a blue berry; foliage spiny or scale-like, or 

 both. The Junipers, ox Red Cedars 



AA. The Deciduous, Broad-leaved Trees. 

 B. Position of leaves opposite. 

 C. Leaves simple. 



D. Fruit winged, i -sided keys in pairs. The Maples 

 DD. Fruit clustered berries. 



E. Flowers 4-parted; berry 2-seeded; leaves 

 not saw-toothed on margins. The Dogwoods 

 EE. Flowers 5-parted; berry, i -seeded; leaves 

 finely saw-toothed on margins. 



The Viburnums 

 DDD. Fruit long, rod-like pods, with thin seeds. 



The Caialpas 

 CC. Leaves compound. 



D. Fruit slender, winged darts in thick clusters; 

 leaflets set along central leaf stem. The Ashes 

 DD. Fruit large nuts in leathery husks; leaflets 



clustered on end of leaf stalk. The Buckeyes 

 BB. Position of leaves alternate. 



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