M ISC ELLA NIES 287 



There are a few cases in which pollen does not seem to be formed 

 abundantly, but these are very few. There are a few cases, 

 also, in which the pistil does not become receptive until after 

 the pollen has lost its vitality; these, however, are very few. 

 In a greater number of cases the pollen is found defective. 

 However, dismissing all of these as the exception, the rule is 

 that self-sterility is due, as has been said, to the lack of affinity 

 between pollen and pistils produced on the vines of some 

 varieties. 



Nature is helpful to the grape-grower in giving a guide to self- 

 fertility. The length of stamens is a fairly safe indication of 

 self-fertility. All grapes which are self-fertile bear flowers 

 with long stamens, although the latter are not a sure sign of 

 self-fertility, as a few varieties with long stamens are self- 

 sterile. On the other hand, short or recurved stamens are 

 always associated with complete or nearly complete self- 

 sterility. 



The remedy for self-sterility is inter-planting. Only the 

 varieties named in Classes I and II in the foregoing classifi- 

 cation should be planted alone. The sorts named in Classes 

 III and IV must be planted near other sorts which bloom 

 at the same time in order that their flowers may be cross- 

 pollinated. 



It is evident that the grape-grower must have some knowledge 

 of the relative time that grapes bloom, if he is to plant intelli- 

 gently to secure cross-pollination. The following table, taken 

 from Bulletin 407 of the New York Agricultural Experiment 

 Station, shows the blooming time of grapes at that Station. 

 Variations due to location and season must be expected, but 

 within the bounds of the regions in which these grapes are 

 grown variations will be slight. When this table is used for 

 other regions than New York, it must be borne in mind that 

 the farther south, the longer the blooming season; the farther 

 north, the shorter the season. 



