74 PRINCIPLES AND PRACTICE OF PRUNING 



heavier deposition of food material in the storage 

 tissues when the tree has formed fruit buds. On the 

 average we found about 4 per cent greater specific gravity 

 of the twigs and branches in winter condition where fruit 

 buds were formed [than where they were absent]. A 

 much larger leaf area is produced in the "off" year than 

 in the bearing year, amounting to 2.08 square inches 

 more to the leaf in the trees studied. 



A second period of fruit bud formation the latter part 

 of sunmier and early fall is e\'idenced by the fruit buds 

 formed on the terminus of the second growth. 



No relationship could be traced between the rainfall of 

 the growing season and the fruit bud formation in this 

 experiment through a period of seven years. . . . The 

 plots where the moisture ran the lowest during the period 

 of fruit bud formation, coupled with good growing con- 

 ditions earlier in the season, produced the largest number 

 of fruit buds. 



Trees receiving cultivation, and cultivation with cover, 

 greatly increased their capacity for fruit bud formation 

 over trees standing in sod. 



The use of fertilizers in addition to cultivation has not 

 as yet increased the fruit bud formation. 



71. Currants and gooseberries bear their fruit buds 

 largely upon shoots which grew "last season" (Figs. 49, 

 50). They also produce spurs which are often so short 

 as to be mistaken for buds. Such spurs are, however, 

 always on wood more than one season old ; in other words 

 a wood bud last season developed a twig perhaps onlv % 

 inch long and produced a terminal cluster bud on this 

 tiny growth. This 3'ear the bud will not only develop 

 leaves and fruits, but will extend more or less and pro- 

 duce one to several cluster buds or wood buds or both 

 kinds. Currant and gooseberry spurs, rarely grow more 

 than 1 inch long, perhaps because the tendency of the 

 plants is to develop fruit on young wood — wood of last 

 season, and two or three seasons ago. Bushes that have 



