

rapes. 



CROSS-FERTILIZATIOIM OF GRAPES. 



PROF. S. B. GREEN, ST. ANTHONY PARK. 



The State Horticultural Society at its last annual meeting- re- 

 quested nie to undertake some experiments with the Moores Early 

 grape to determine, if possible, why it was generally such a shy 

 bearer, and, especially, to study its flowers and the necessity for 

 cross-fertilizing them: it being believed by many that this variety 

 was more fruitful when furnished with foreign pollen than when 

 entirely dependent on its own. In working out this special line, it 

 was decided to experiment with the cross and self-fertilization of 

 other varieties, as well as the Moores Early. 



The experiments made were as follows : On June 16th, the flowers 

 of the grapes being then not open, six bunches each of Moores 

 Early, Brighton, Agawam, Ives Seedling and Lindley were covered 

 with paper bags which were carefully pinned over the branch above 

 the bunch. By this means the enclosed clusters were protected 

 from pollen of other kinds, which would naturally be conveyed to 

 them by insects and, perhaps, by the wind. 



When the flowers of the different kinds had opened and the stigma 

 was in proper condition, three of the bags of each kind were opened 

 and a cluster of the opened flowers of the Delaware grape inserted 

 in them. Thus, there were of each variety three bunches of flowers 

 that were cross-fertilized and three that were self-fertilized. These 

 were allowed to grow without being disturbed until the berries 

 were about one-half inch in diameter, when examination showed 

 that Moores Early, Ives Seedling, Lady and Agawam had set fruit 

 perfectly, whether dependent on their own pollen or cross-fertilized. 

 The Lindley and Brighton, however, while setting fruit perfectly 



when cross-fertilized, did not 

 produce any fruit whatever 

 when dependent on their own 

 pollen, but the whole cluster 

 withered awa3^ This is very 

 clearly shown in the plate here- 

 with, in which the clusters in 

 the upper row are from bags in 

 wnich foreign pollen was in- 

 troduced, while the lower roAv 

 shows the clusters from bags 

 awani. 4, Lady, which had no foreign pollen. 

 The results show plainly that 

 the Moores Early produces an 

 abundance of pollen for its own use under the conditions imposed 

 in this experiment. An examination of its blossoms and fruit indi- 

 cates that there is an abundance of pollen to fertilize the stigmas 



I, Brighton 

 5, Worden. 6, Moores 

 Upper row cross-fertilized. 

 Lower row dependent on its own pollen. 



Lindley. 



Early, 



