16 



SEED FOR PROPAGATION 



are used. The English or Persian walnuts are either 

 grafted on their own seedlings or on those of the Black 

 Walnuts. The latter is preferred because of its hardiness 

 and resistance to certain diseases. In the moist sections, 

 the Eastern Black Walnut is used, while in the arid regions 

 the Arizona Black or California Black are used because of 

 their adaptability to the drier conditions. Pecans are 

 worked on the more hardy native seedlings. Many of these 



Olive - Olea europa 



Spanish Chestnut - Castena vesca 



Pecan-Hicoria pecan ' Hicoria ovata 



YIG. 6. Some of the Less Common Tree Fruit Seed. 



nuts are grown as seedlings, because only in recent years has 

 any definite effort been made to develop better varieties, 

 and the nearer any variety is to the native or wild con- 

 dition the less the need for any special stock. 



Chestnuts are usually worked upon the native American 

 stock. Many of these are still grown as seedlings, there 

 having been little effort toward improved strains. The 

 hickories, butternuts, filberts and other wild nuts are almost 

 entirely grown direct from seed, there being no need of 



