250 



The Trees of Great Britain and Ireland 



Key to the Species of Juglans in Cultivation 

 I Leaflets not serrate ; usually entire or sinuate (Plate 73). 



X. Juglans regia^ Linnaeus. Bosnia and Greece, through W. Asia and Himalayas 



to N. China. . 



Leaf-scars deeply notched without a pubescent band on their upper edge. 

 Leaflets 7 to 9, glabrous beneath except for inconspicuous axil tufts. 



1 1 . Leaflets serrate. Leaf -scars without a pubescent band on their upper edge. 

 * Leaflets glabrous beneath, except for the axil tufts. 

 2. Juglans regta^ nigral Two forms: Juglans Vilmorimana, Carriere, and 

 Jtiglans pyriformis, Carriere. 

 Leaflets 11 to 13, with fine shallow serrations. 

 ** Leaflets pubescent beneath. 

 . 3. Juglans rupestris, Engelmann. Arizona, Texas, New Mexico, Mexico. 



Leaflets small, 7 to 1 5, ovate or lanceolate, never oblong, green beneath. 

 Young shoots glandular-pubescent. 



4. Juglans nigra, Linnaeus. Canada and United States, east of the Rocky 



Mountains. 

 Leaflets large, 15 to 19, ovate-oblong with long-acuminate apex, pale beneath. 

 Young shoots glandular-pubescent. 



5. Juglans stenocarpa, Maximowicz. Manchuria, 



Leaflets large, 11 to 13 ; all oblong, except the terminal one which is broadly 

 obovate, pale beneath. Young shoots glabrous. 



in. Leaflets serrate. Leaf -scars with a transverse pubescent band on their upper 

 edge. 



6. Juglans cinerea, Linnaeus. Canada and United States, east of the Rocky 



Mountains. 

 Leaf-scars semicircular, the upper edge straight and scarcely notched. Leaflets, 

 II to 13, oblong; serrations fine and directed outwards. 



7. Juglans Sieboldiana^ Maximowicz. Japan, Saghalien. 



Leaf-scars obcordate, 3-lobed, notched above. Leaflets, 13 to 15, oblong; 

 serrations shallow, irregular, directed forwards ; base rounded and unequal. 



8. Juglans viands hurica,^ Maximowicz. Manchuria, Korea, China. 



Leaflets and leaf-scars practically indistinguishable from those of the last 

 species, though the leaflets are usually longer-acuminate. Fruit, however, 

 remarkably distinct. See detailed description. 



9. Juglans cordiformis^ Maximowicz. Japan. 



Leaf-scars and leaflets closely resembling those of J. Sieboldiana, the leaflets, 

 however, fewer (11 to 13) and with a cordate base. 



' These three species, though differing remarkably in fruit, are very similar in leaves and shoots, 



