no 



MINNESOTA STATE HORTICULTURAL SOCIETY. 



order to insure cross-fertilization the stigma becomes receptive 

 either before the pollen is shed or after it has all been blown away. 

 In either case the chances for cross-pollination are much greater 

 than in -the case when the pollen is shed at the same time that the 

 stigma becomes receptive. In hand-pollinating we must know the 

 structure of the flower, and we must be able, with the aid of a 

 lens, to tell just when the anthers open or when the stigma be- 

 comes receptive. It is known that the stigma is receptive when a 

 viscid transparent substance appears on its surface. 



In crossing the main thing, of course, is to get the pollen of one 

 flower onto the stigma of the other and just at the right time. The 

 parents should be selected with a distinct ideal in mind. To avoid 



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self-fertilization or pollination from any other source we must 

 take various precautions. The flower which is to be the female 

 parent is emasculated a day or so before it would open, i. e., the 

 bud is opened by hand, with or without the aid of instruments, 

 and all the stamens are cut out and removed entirely. In the case 

 of strawberry flowers this can be done best with the thumb nails, 

 and it works better and quicker than if a scalpel or tweezers are 

 used. It is essential that the anthers should be removed before 

 they open, and no pollen should be allowed to escape in the process 

 of emasculation. This act prevents* self-fertilization. But we 

 must also prevent any other pollen from alighting on this stigma, 

 either by wind or insect, and so we cover the emasculated flower 



