BETULACEAE 23 



homogeneous sometimes dark pith; alternate low shield-shaped 

 large leaf-scars with 3 more or less confluent groups 1 of bundle- 

 traces; no stipule scars; alternate ovoid often superposed 

 rather large buds sometimes stalked or developing the first 

 season; large odd-pinnate leaves; small green monoecious 

 apetalous flowers in catkins or small clusters; and rather large 

 nuts with loose usually dehiscent husk. (Hicoria). 



1. Bud-scales in pairs, sometimes developing into small leaves: 



lateral buds often stalked. (Pecans and Bitternuts 1 ) . 2. 

 Bud-scales not in opposite pairs. 3. 



2. Twigs and buds with yellow glands': nut scarcely elongated, 



mamillated, very thin-shelled, very bitter. C. cordiformis. 

 Twigs scarcely glandular: nut longer than thick, rather firm- 

 shelled, not bitter. (Pecan). C. Pecan. 



3. Terminal bud small (scarcely 10 mm. long). (Pignuts). 4. 

 Terminal bud large (usually over 10 mm.). (Hickories). 5 



4. Leaves glabrate: bark not deeply fissured. C. ovalis. 

 Leaves hairy: bark deeply fissured into squares. C. villosa. 



5. Outer bud-scales falling: not shaggy. (Mockernut). C. alba. 

 Outer scales persistent, pointed: bark shaggy. 6. 



6. Twigs buff or orange: leaflets 7-9. (King-nut). C. laciniosa. 

 Twigs gray or reddish: leaflets usually five. 7. 



7. Twigs glabrate. (Shagbark hickory). C. ovata. 

 Twigs persistently hairy. (Hairy Shagbark) .O. ovata hirsuta. 



Family BETULACEAE. Birch Family. 

 A small family chiefly of cold regions, furnishing some 

 important lumber and the hazel nuts and filberts of commerce; 

 much planted for single tree effect. 



CORYLUS. Hazel. Filbert. 



Deciduous shrubs with light brown wood with minute ducts 

 in radial or flame like patterns and very fine medullary rays; 

 moderately slender rounded often bristly twigs; roundish 

 homogeneous pale pith; alternate low crescent-shaped leaf- 

 scars with 3 often compound bundle-traces; narrow stipule- 

 scars ; ovoid buds with half-a-dozen exposed scales, the end bud 



