522 B.EPOKT OF THE HORTICULTURIST OP THE 



3-pound to 5-pound sizes "being preferred. The smaller sizes may 

 cramp the larger clusters and the larger sizes offer too much resist- 

 ance to the wind. The shoots on which the clusters are borne 

 being still green and tender at blooming time are more liable to 

 be broken off in wind storms when the large bags are attached to # 

 them than they are when the smaller sizes are used. 



In preparing a bag for covering a cluster it is slit downward 

 from the mouth for a short distance on opposite- sides so that the 

 open end may include and project beyond the shoot on which the 

 cluster is borne as shown in Figure 1. The mouth is then closed 

 and fastened with a wired label as shown by Figure 2. In this way 

 a portion of the shoot is included which holds the bag more firmly 

 than when it is fastened to the stem of the cluster only and the 

 cluster is less apt to be broken off. 



NUMBER OF VINES AND CLUSTERS TESTED. 



Number of clusters. — The number of clusters tested among the 

 cultivated grapes varies from four to seventy-one and averages 

 about fifteen to the variety. This does not include the varieties 

 Little Blue, Norfolk and Illinois City. No account is taken of 

 clusters which have been lost or destroyed by accident. 



Number of vines. — ISTo exact record has been kept of the num- 

 ber of vines tested to the variety. It varies from one to perhaps 

 ten or more. Probably in the majority of cases at least two vines 

 have been tested to the variety. 



Tests of but few clusters. — Are tests of two or three clusters 

 on a single vine sufficient to show the characteristic degree of self- 

 fertility of a variety? The records of these tests give some evi- 

 dence on this question. Nineteen varieties were tested by cover- 

 ing only two clusters of each in one season. The same varieties 

 were afterwards tested by covering a larger number of clusters. 

 The latter tests gave results practically similar to those of the first 

 tests except in the case of three Rogers hybrids which in the first 

 tests gave only perfect clusters and in the later tests gave some 



