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UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 



distribution by wind and insects much less certain. The pollen grains 

 are, moreover, often imperfect, and most of them are incapable of 

 germination and performing their function, even if they reach the 

 stigma. 



This is shown when we place the pollen grains in a weak sugar 

 solution. Normal pollen germinates readily in such a solution, but 



that of Muscat of 

 Alexandria germi- 

 nates irregularly, 

 imperfectly, or not 

 at all. The same 

 result occurs if the 

 pollen is placed on 

 the stigma of any 

 variety of vine. 



Remedies. - - In 

 regions where this 

 variety has been 

 grown for centu- 

 ries (Asia Minor, 

 northern Africa, 

 Spain) it is usual 

 to plant other 

 varieties having 

 abundant and 

 strong pollen 

 among the Muscat 

 vines. This prac- 

 tice, while not re- 

 moving the trouble 

 completely, may be 

 of use in Califor- 

 nia. It would be 

 well in planting a 

 Muscat vineyard to 

 make use of some 

 of the varieties which have shown their ability to produce abundant 

 and vigorous pollen. The proof of this is regular setting of abundant 

 crops. The pollinating varieties might be planted in neighboring blocks, 

 or, better still, in occasional rows. 



It is necessary not only that the pollinating varieties should have 

 good pollen, but that they should blossom at the same time as the 



FIG. 20. Four-year old Muscat of proper form. 



