THE MONTHLY BULLETIN. 451 



explain the greater fruitfiilness of some dwarf apples and pears. On 

 the other hand, a species or a variety may be too weak in growth to 

 be fruitful, in which case grafting on a stock which imparts vigor may 

 make them more productive. 



Sixth — The time of maturity of both wood and crop may be 

 changed somewhat by the stock — hastened on the one hand or re- 

 tarded on the other, according as to whether the stock ripens earlier or 

 later than the scion. It follows, of course, that the keeping quality is 

 affected in the same degree as maturity. Thus, it is found that oranges 

 on Trifoliata ripen earlier than on other stocks. The statement is 

 common in literature that many late fruits budded on early ones ripen 

 earlier and that .some early fruits on late varieties, ripen later. It seems 

 from what is known on this subject that we are warranted in saying that 

 earliness is promoted in the scion only, however, when the stock ripens 

 its wood earlier than the scion ; lateness, when the stock ripens its wood 

 later. 



Seventh — The color of a fruit may be changed by the stock. There 

 is little evidence to substantiate the claim often made that the character- 

 istic color of a fniit is changed by the stock, but, as all know, color is 

 heightened bj' earliness and lessened by lateness in the maturity of a 

 variety. In the cases, then, in which the stock influences the time of 

 maturity the color may be more or less changed. The speaker knows of 

 an orchard of jMcInto.sh apples which are grafted on Oldenburg, the 

 fruits of which mature nearly two weeks earlier than ]\IcIntosh on 

 standard stocks and are much higher in color. 



Eighth — The size of a fruit is often increased by the stock. I need 

 only to cite the pear on the (juince as an example, though many other 

 illustrations might be adducecl. 



Ninth — Rather reluctantly, from my point of view, we must accept 

 the testimony that the stock affects the flavor of the fruit home on the 

 scion. It is not hard to believe that larger, crisper, juicier fruits of 

 a variety can be grown on some stocks than on others and that, there- 

 fore, the flavor is improved. But how a sour variety grafted on the 

 stock of a sweet one, or the reverse, can change the degree of sweetness 

 or sourness is past understanding, yet an abundance of evidence seems 

 to prove such changes sometimes to be the case. 



Tenth — Some stocks shorten the life of the trees of which they are 

 a part. Apples on pears and pears on apples are short-lived trees. 

 Common pears, Pyrus communis, are short-lived on the Chinese pear. 

 Pijrus sinensis. It may be laid do^Mi as a rule to which there are but 

 few exceptions, that grafting a weak-growing species on a vigorous stock 

 will result in a short-lived tree. 



So far we have been discussing tree fruits. Much more is known 

 about the influence of the stock on the scion in grape growing, as you 

 in California with your reconstructed vineyards should know. To 

 briefly epitomize : Experimenters hold, and I quote only from those of 

 established reputation, that there are very appreciable differences to be 

 noted between the chemical and physical composition of grapes grafted 

 on various stocks and the fruit of vines on their own roots. Among the 

 effects claimed for grafting, I note but do not vouch for the following: 

 The fruit of the grafted vines is larger, has bigger seeds, thinner skin, 

 the berries are less numerous, the juice is more copious, is usually both 

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