54 INFLUENCE OF THE SOIL AND STOCK. 



depth, and other characters of soils may do the same. Ten- 

 der kinds are made hardier on hardy stocks, not because of 

 any specific influence, but the usual supplies of sap are im- 

 parted sooner in spring and withheld earlier in autumn, and 

 the tender wood has more time to mature precisely similar 

 to the planting of tender trees on sterile or rocky soils, which 

 cause an earlier cessation of growth. 



Although, as a general rule, the change in quality is so 

 small as to be rarely taken into account in practice, it is in 

 some rare instances considerable, and is worthy of investiga- 

 tion and experiment. Early fruits have been sometim'es 

 retarded a few days in ripening when grafted upon late va- 

 rieties of their own species, and their maturity has been 

 hastened on early stocks. In one case, the JRed Magnum 

 Bonum plum ripened ten days earlier when grafted on the 

 Cherry plum, a variety which matures at midsummer, than 

 when worked upon a late prune. In another instance, late 

 peach stocks were found to retard a few days the sorts bud- 

 ded upon them.* 



In one instance,, related by President Knight, a very 

 marked change was effected. His garden contained two 

 trees of the Acton Scott peach, one growing upon a stock 

 of its own species, and the other on a plum, other circum- 

 stances being the same. The fruit of that upon the plum 

 was larger and much more red to the sun ; but its pulp was 

 coarse, arid its flavor so inferior that he would have denied 

 the identity of the variety had he not himself inserted the 

 buds. Such remarkable instances are to be regarded as of 

 very rare occurrence. 



Salt peaches or plums, show that foreign substances may 

 enter the juices, and modify or change the quality of the 

 fruit, as well as poison or induce disease in the tree. Solu- 

 ble substances in the soil may thus exert a sensible influ- 

 ence. In the same way, the peculiar character of the sap 

 and secretions of a stock may produce a like result. 



The, increased productiveness effected by dissimilar stocks, 

 is often so great as to become a very important object in 

 practice. "In proportion," says Lindley, "as the scion 

 and the stock approach each other closely in constitution, 

 the less effect is produced by the latter ; and on the contra- 



* Hort., III., p. 191. 



