334 JUGLANDACEAE 



flattened. Seed sweet or bitter. [Carya Nutt.] The plants flower in the spring and 

 mature their fruit in the fall. HICKORY. 



Cotyledons entire or merely notched at the apex: nuts terete or slightly flattened, smooth and even. 

 Leaflets 5-9: nuts with exceedingly thick shells: calyx-lobes 



obtuse. 1. H. myristicaeformis. 



Leaflets 9-15: nuts with thin shells: calyx-lobes acute. 



Leaflets with stalked blao.es: nut terete: seed sweet. 2. H. Pecan. 



Leaflets with sessile or nearly sessile blades : nut flattened : 



seed bitter. 3. H. Texana. 



Cotyledons deeply 2-lobed: nuts markedly flattened, usually un- 

 even. 

 Bud-scales valvate: lateral leaflets mostly falcate. 



Leaflets 9-13, glabrous: nuts corrugated. 4. H. aquatica. 



Leaflets 5-9, pubescent beneath: nuts smooth. 5. H. cordiformis. 



Bud-scales imbricated: lateral leaflets not falcate. 



* Middle lobe of the staminate calyx, much longer than the 

 lateral: husk of the fruit freely splitting to the base. 

 Bark close, but rough: foliage scurfy or pubescent. 

 Rachis of the leaves and staminate aments scurfy 



pubescent at least when young. 6. H. pallida. 



Rachis of the leaves and staminate aments densely 



hirsute. 7. H. alba. 



Bark shaggy, separating in long plates: foliage glabrous 



or puberulent. 



Leaflets 79: nuts pointed at both ends. 8. H. laciniosa. 



Leaflets 3-5: nuts rounded or notched at the base. 

 Twigs and lower surface of the leaflets puberu- 

 lent. 9. H. ovata. 

 Twigs and lower surface of the leaflets glabrous 



or glaucous. 10. H. Carolinae-septentrionalis. 



** Middle lobe of the staminate calyx about equal to the 

 lateral, except in No. 12: husk of the fruit not 

 freely splitting to the base. 

 Bark shaggy: fruit mostly subglobose: nut thin-shelled: 



seed sweet. 11. H. microcarpa. 



Bark close : fruit mostly obovoid : nut thick-shelled : seed 



bitter. 

 Foliage glabrous: staminate calyx with an elongated 



acute middle lobe: anther-sacs acute. 12. H. glabra. 



Foliage pubescent: staminate calyx with a short 



blunt middle lobe: anther-sacs obtuse. 13. H. villosa. 



1. Hicoria myristicaeformis (Michx. f.) Britton. Tree becoming 35 m. tall, 

 the bark scaly: leaflets 5-9, the blades usually oblong-lanceolate, to ovate-lanceolate, 

 5-12 cm. long: 2 staminate aments 6-10 cm. long: fruits elliptic or elliptic-obovoid, 

 2.5-3.5 cm. long. 



In low grounds or on hillsides, South Carolina and Arkansas to Alabama, Texas and 

 Mexico. 



2. Hicoria Pecan (Marsh.) Britton. Tree becoming 50 m. tall, the bark some- 

 what roughened: leaflets 11-15, the blades falcate, oblong-lanceolate, 8-15 cm. long: 

 staminate aments 12-15 cm. long: fruits oblong, 3.5-6 cm. long. 



In moist soil and along streams, Iowa to Kentucky and Texas, and introduced into the 

 other Gulf States. PECAN. 



3. Hicoria Texana LeConte. Tree becoming 20 m. tall, the bark rough: 

 leaflets 9-13, the blades lanceolate to oblong-lanceolate, 8-15 cm. long: staminate 

 aments 5-11 cm. long: fruits oblong, 3.5-5 cm. long. 



In low grounds or river swamps, Texas. 



4. Hicoria aquatica (Michx. f.) Britton. Tree becoming 30 m. tall, the bark 

 flaky: leaflets 9-13, the blades of the lateral ones lanceolate, 5-15 cm. long, falcate: 

 staminate aments 7-10 cm. long: fruits subglobose, but beaked, 2.5-3 cm. thick, 

 the thin husk tardily 4-valved: nut corrugated, thin-shelled, the seed bitter. 



In river swamps and wet woods, Virginia to Illinois, Florida and Texas. WATER 

 HICKORY. 



5. Hicoria cordiformis (Wang.) Britton. Tree becoming 30 m. tall, the bark 

 close, with shallow furrows and flat ridges: leaflets 5-9, the blades of the lateral ones 

 lanceolate or oblong-lanceolate 8-15 cm. long, falcate: staminate aments 7.5-10 cm. 

 long: fruits subglobose, 2.5-3 cm. long, slightly 6-ridged, the thin husk tardily 4- 

 valved: nut smooth, thin-walled, the seed bitter. 



In swamps and low woods, Quebec to Minnesota, Florida and Texas. SWAMP HICKORY. 

 BITTER-NUT. WHITE HICKORY. 



