536 



GROWING BUSH FRUITS 



mercial varieties of these fruits are productive when planted in 

 solid blocks, even at great distances from other varieties, is 

 sufficient evidence that the pollination problem, if any, is a 

 very minor one with them. 



Practically all the common blackberry varieties are self- 

 fruitful. There are a few hybrid varieties, however, such as 

 McDonald, Rathhun, Spaulding, and Wilson which do not 

 ^^set" well with their own pollen. Such varieties should not bo 



Fig. 226. Red raspberries grown in hedge rows without stakes or trellig. 

 The canes have been clipped shorter than in Figs. 227 and 228. 



planted by themselves, but with some other variety so that 

 suitable pollen will be available for cross-pollination purposes. 

 The Mammoth and Cory Thornless varieties have also been 

 found to be more or less self-unfruitful under Oregon condi- 

 tions, and it is suggested that provision should be made for 

 cross-pollination if these varieties are grown. 



Most of the commercial varieties of dewberries such as 

 Lucretia, Mayes (Austin), and Young are self-fruitful, but 

 certain varieties as Premo, Chestnut, Grandee, Munroe, and 

 San Jacinto have been found to be self -unfruitful. In these 



