INFLUENCE OF CION AND STOCK. 75 



3. Graftage may be made the means of adapting plants 

 to adverse climate. This may be brought about by either 

 or both of two causes : {a) The early maturation of the 

 stock, causing the cion to ripen better. The Oldenburgh 

 apple is a favorite stock in severe climates for this reason. 

 The Siberian crab often has the same influence, although 

 its use may be open to objection, (d) The mechanical 

 effect of the union, impeding the passage of sap and 

 causing the cion to mature or ripen early. This fact has 

 been observed in many cases, notably in some instances 

 of apples upon improved crabs, and yet the union is perfect 

 enough, nevertheless, to maintain the plant in a profitable 

 condition for years. There are some apparent adaptations 

 to climate, however, which are not explained by either of 

 the above hypotheses. 



4. Graftage may correct a poor habit. All propaga- 

 tors are aware of this fact. The Canada Red apple is 

 usually top-worked to overcome its weak and straggling 

 habit. The Winter Nelis pear is a familiar example. 



5. Graftage is often the means of accelerating fruitful- 

 ness : i. e., plants are made to bear at an earlier age. 

 Those who test new orchard fruits are familiar with this 

 fact. Cions from young trees bear sooner if set in old 

 trees than when set in young ones. This result may some- 

 times be due to the same causes which abbreviate the vigor 

 of plants, as already outlined (see ? 3, above). Checking 

 growth induces fruitfulness. 



6. Graftage often modifies the season of ripening of 

 fruit. This is brought about by different habits of matur- 

 ity of growth in the stock and cion. An experiment with 

 Winter Nelis pear showed that fruit kept longer when 

 grown upon Bloodgood stocks than when grown upon 

 Flemish Beauty stocks. The latter stocks in this case 

 evidently completed their growth sooner than the others. 

 Twenty Ounce apple has been known to ripen in advance 

 of its season by being worked upon Early Harvest. Mr. 

 Augur cites an instance in which the Roxbury Russet, 



