THE AMERICAN WALNUTS 



703 



vated in the eastern United States, and is hardy as far 

 north as Massachusetts. It is also cultivated to a limited 

 extent in Europe, but no extensive introductions have 

 yet been made either in Europe or the eastern United 

 States. 



The two western species of Walnut may be distin- 

 guished by the following distinguishing characteristics : 



CALIFORNI.\ WALNUT 



(1) Leaves with II to 17 leaflets. 



(2) Leaflets 1}4 to 3 inches long, 

 and y^ to H oi an inch wide. 



(3) Nut obscurely grooved. 



(4) Nuts with rather thin shells. 



(5) Native to California. 



SOUTHWESTERN WALNUT 



(O Leaves with 9 to 23 leaflets. 



(2) Leaflets 2>4 to 5 inches long 

 and 1-3 to V/2 inches wide, 



(3) Nut deeply grooved. 



(4) Nuts with rather thick shells. 



(5) Native to Southwest. 



In addition to the native Walnuts, a few foreign spe- 

 cies have been introduced. The English or Persian Wal- 



THE BUTTERNUT 



1. Branch with one-half developed leaves, (s) 3 unbranched cat- 



kins of staminate flowers, and (p) a cluster of pistillate 

 flowers, X yi. 



2. A mature leaflet, x yi. 



3. A staminate flower, slightly enlarged. 



4. A pistillate flower, slightly enlarged. 



5. A cluster of mature fruit, x 1/2. 



6. A winter twig showing buds, lenticels, leaf scars, and pith, x ]^ 



7. Longitudinal section of twig showing chambered pith, slightly 



enlarged. 



8. Section of winter branch showing leaf-scars, hairy fringe 



above leaf-scars and superposed buds, slightly enlarged. 



9. A nut with husk removed, x yi. 



10. A terminal bud, natural size. 



11. A terminal bud (broad-side view), natural size. 



12. Section of a branch showing superposed lateral flower buds, 



enlarged. 



LEAF OF THE ENGLISH WALNUT 



The English or Persian Walnut is a valuable economic tree as 

 its fruit is about the most widely used of the walnuts and its 

 wood is the highly valued Circassian Walnut of commerce. 

 The foliage is very beautiful. 



nut is more 

 widely d i s - 

 tributed than 

 any other for- 

 eign Walnut 

 It is now pro- 

 pagated prof- 

 i t a b 1 y in 

 southern Cal- 

 ifornia and a 

 considerab 1 e 

 degree of suc- 

 cess has been 

 had with its 

 cultivation in 

 the Mississip- 

 pi Valley and 

 the milder 

 parts of the 

 eastern Unit- 

 ed States. It 

 is 



A TWO-YEAR OLD SEEDLING 



rather "^^^^ '^ * ^^^ young black walnut growing on 

 a plantation in northern Pennsylvania. 



