Key to the Principal Tree Families 



C. Leaves simple. 



D. Bases of leaves symmetrical. 



E. Fruit fleshy, globular, more or less edible. 

 F. Seeds solitary. 



G. Margins of leaves saw-toothed. 



The. Plums and Cherries 

 GG. Margins of leaves not sav^-toothed. 



The Tiipelos 

 FF. Seeds several in walled cells. 

 G. Cores papery. 



H. Fruit small, berry-like. 



The Juneberries 

 HH. Fruit large. The Apples 



GG. Cores bony; fruit thin fleshed. 



The Hawthorns 

 EE. Fruits dry. 



F. Seeds borne in protecting cups or 

 burs. 

 G. Burs scaly, not opening when ripe; 

 nut conical. The Oaks 



GG. Burs spiny, 4-valved, opening when 

 ripe. 

 H. Nuts triangular, small. The Beech 

 HH. Nuts conical, larger. The Chestnut 

 FF. Seeds borne in swinging balls. 

 J G. Leaves star shaped; branches corky 



ridged. The Sweet Gum 



GG. Leaves broad, 3 to 5-Iobed, bark shed 

 in sheets, leaving pale, irregular 

 patches. 



The Sycamore, or Buttonwood 

 FFF. Seeds borne in cone-like heads. 

 G. Bark in horizontal sheets. 



The Birches 

 GG. Bark smooth; leaves large, leathery. 

 H. Leaves pointed at tip; seeds 

 scarlet, berry-like, on elastic 

 threads. The Magnolias 



HH. Leaves truncate at apex; seeds 

 dry, with long, flat wing. 



The Tulip Tree 

 FFFF. Seeds borne in 2-valved pods on elon- 

 gated catkins; minute and hid in cot- 

 tony down. 

 G. Leaves narrow; branches supple. 



The IVillows 

 GG. Leaves broad; leaf stalks flat, 



branches stiff, angular. The Poplars 



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