LEAVES, BUDS AND FLOWERS 



95 



productive. The hop plant, persimmon and date palm 

 are of this class. 



The flowers of many of our most productive varieties 

 of strawberry yield lit- 

 tle or no pollen and 

 are unproductive, unless 

 growing near pollen- 

 bearing sorts (Figs. 56, 

 57) . In many varieties 

 of American plums and 

 in certain varieties of 

 the pear and apple, the 

 pollen, even though pro- 

 duced freely, is infertile 

 on stigmas of the same 

 variety. To insure fe- 

 cundation, it is wise to mingle varieties in fruit plan- 

 tations rather than to plant large blocks of a single 

 variety. 



Fig. 56. 



Fig. 57. 



Fig. 56. — Imperfect flower of the straw- 

 berry. 



Fig. 57. — Perfect flower of same. The 

 numerous pistils appear in a circular 

 mass at the center, around which the 

 stamens are seen. 



