105 



for food. The most valuable and edible nuts are obtained from the 

 Shag-bark Hickory (Carya ovata). 



This genus comprises about 10 species found in eastern North 

 America and 1 species in Mexico. Six species are native to this 

 State. One species, the small-fruited Hickory (Carya microcarpa, 

 Nutt. ), sometimes considered a variety of the Pignut Hickory, is found 

 locally in the State but not described in this publication. In addi- 

 tion to our native specie.s the Pecan Hickory (Carya illinoensis) is 

 planted extensively for ornamental purposes and for the sweet nuts 

 which it prodtfces. 



SUMMER KEY TO THE SPECIES. 



Page. 

 1. Leaflets 7-H, small, lancpolate, usually curved C. cordiformis 110 



1. Leaflets 3-7, larger, broader than lanceolate, rarely curved 2 



2. Husk of fruit splits tardily into 4 valves; valves of fruit thin and rather friable at 



maturity; twigs smooth, relatively slender, cherry colored to gray C. glabra lOD 



2, Husk of fruit splits promptly into 4 valves; valves of fruit thick and hard at 



maturity; twigs often hairy towards tip, rather stout, buff, gray, or brownish 3 



3. Bark closo, rough but not shaggy on old trunks; twigs relatively stout; foliage scurfy 



or pubescent C. alba lOS 



3. Bark shaggy separating into Ion,; plates on old trunks; tvfigs not so stout; foliage 



smooth or sometimes downy beneath ^ 



4. Leaflets usually 7; nuts dull white or yellowish and pointed at both ends, C. laciniosa 107 

 4. Leaflets nsually 5; nuts white, rounded or notched at the Imse, C. ovata 10€ 



WINTER KEY TO THE SPECIES. 



1. Buds yelicw with 4-6 budscales valvate in pairs; lateral buds often evidently- 

 stalked; terminal buds elongated and flattened C. cordiformis HO 



1. Buds not yellow, truly scaly: bud-scales 10 or more usually overlapping, except outer 



ones on lateral buds vhich may form a closed sac but in time split from the 

 top; inner scales hairy, 2 



2. Buds small; terminal buds \/'^ to 2/5 of an incli long, their outer scales glnndulnr 



dotted: twigs smooth, relatively slender, cherry-colored to gray; husk of fruit 



thin, not freely splitting to base, with thin-shelled nut C. glabra 109 



2. Buds large; terminal I'uds 2/5 to 3/.1 of an inch long, their outer scales almost 



glandless; twigs often hairy towards tip, rather stout, buff, gray, or brownish; 

 husk of fruit thick, freely splitting to base 8 



3. Twigs relstively stout; bark rough and close, not shaggy; nnt brownish, thick- 



shelled, with small kernel; terminal buds broadly-ovate with their outer scales 



early deciduous C. alba 108 



3. Twigs not so stout; bark shaggy: nut w-hite, dull-white, or yellowish with large 



kernel: terminal buds elongate-ovate with their outer scales tardily deciduous 4 



4. Nuts dull white or yellowish and pointed at both ends C. laciniosa 107 



4. Nuts white, rounded or notched at the base C. ovata 106 



