320 



Keport of the Horticulturist of the 



PRODUCTIVENESS OF GRAPES AS AFFECTED BY 

 SELF-FERTILIZATION OF THEIR BLOSSOMS. 



Many kinds of grapes are unable to set fruit when standing alone, 

 others are apt to produce abortive berries and imperfect clusters, 

 while still others produce satisfactory clusters. Some of the kinds 

 which can not set any fruit or which do not form satisfactory clus- 

 ters when standing alone, are able to set fruit when their blossoms 

 are fertilized by pollen from other varieties of grapes. So it hap- 

 pens that some kinds of grapes do very well when they are mingled 

 with other varieties, but when planted in blocks by themselves they 

 either do not bear at all or the yield is unsatsfactory. 



It is a matter of practical importance to grape growers to know 

 which kinds of grapes can set fruit satisfactorily when standing alone 

 and which can not. Investigations on this subject were begun at 

 this Station in 1892 and have been continued each succeeding season 

 so far as time and opportunity permitted. Some account of this work 

 is given in this Station's reports 1892: 597-606. 1894: 636-648. 



The experiments thus far have been conducted solely in the Sta- 

 tion's vineyards. The method of investigation has been to cover 

 the clusters of unopened flower buds with paper bags so as to exclude 

 all outside pollen. In 1895, 610 clusters distributed among 80 vari- 



