Tkkes of the Xokthekn United States 1<»7 



Xr.t elongated, almost terete, seed sweet; leaflets ll-l-\ 

 ineciuilateral, acuminate. //. pecan. 



2. Xut somewhat compressed or angled, usually as broad 



as long; seed intensely bitter; lateral leaflets falcate. 8. 



3. Leaflets 7-11 ; nut smooth ; husk thin, splitting to below 



the middle. //. curdiforniis. 

 •"). Leaflets i'-13; nut angled, husk thin, splitting to the base. 

 //. aqiialica. 



4. Terminal l)ud large, ]-[ in. long; husk splitting freely 



to the l)ase, nut angled, seed sweet ; middle lobe of 



the staminate calyx narrow, often at least twice as 



long as the lateral ones. 5. 

 1. Terminal l)ud small. ]-•] in. long; liusk thin, not splitting 



freel}- io the base, nut slightly or not angled; lobes 



of the staminate calyx mostly nearly equal. 8. 

 •'i. I'.ark shaggy. sei)arating in long plates; husk ver}' thick. 



splitting to the l)ase ; outer bud-scales i)ersisting 



through the winter. C). 

 h. !)ark close, rough; leaflets "-!', stellate puliescent ; outer 



bud scales falling away in autumn ; husk not separat- 

 ing" quite to the liase ; twigs and petioles tomentose. 



//. alha. 

 li. Leaflets •"i-'), rarely 7. nut rounded at the base-, h-l in. 



long. 7. • 



(i. Leaflets 7-!i; nut usually pointed at both ends. \-\\ in. 



long. //. laciiiiosa. 

 7. Leaflets oblong-lanceolate to obovate : twigs puberulent. 



//. ovata. 

 7. Leaflets narrowly lanceolate; twigs glaucous. //. car(^- 



Jinac-scpicntrionaJis. 

 !<. l'"ruit nearly globular; nut thin-shelled; bark of old trees 



sci)arating in stri])s ; leaflets ')-7. //. luicrocarfa. 

 S. Fruit ol3o\oid: nut thick-shelled; liark close. !'. 

 !>. Leaves glabrous or nearly so; leaflets -^-7. rarely •'! or !'. 



//. glabra. 

 !t. Leaves with sil\er\- peltate glands ; leaflets •")-!•. //. 



r'lUosa. 



1. Hicoria pecan (.Marsh.) IJritt. IVcan (Hickory). 

 A large tree of rapid growth with rough l)ark and a long 

 tap r(^ot. Leaflets 11-1-V (iI>1(^ng-lanceolate. short-stalked, in- 



