Growth 317 



It is quite possible that many trees show types of de- 

 velopment from the resting bud dependent upon the con- 

 ditions. In the Carolina poplar the writer has found that 

 old trees may show an exfoliation of few if any more leaves 

 than are normally contained in the bud, while younger 

 trees in rapid growth may produce more than five times 

 as many as were thus preformed. 



Frequently the leaves of the apple, pear, peach, and 

 other fruits seem to be produced in clusters upon short 

 branches or spurs; in those cases, as a rule, the internodes 

 are suppressed, and the axis is therefore greatly shortened. 

 This is particularly common on fruit spurs. It is impos- 

 sible here to consider the modifications in growth accom- 

 panying fruit production, the alternations of growth, 

 elongation, fruiting, 1 etc. 



184. Fruit buds and age of shoot. It is of importance 

 to consider briefly the relation of fruit buds to the age of 

 the wood in a few economic plants. In the grape, the 

 fruit is borne on canes produced during the current year. 

 Where a vine is left for a season unpruned, many buds 

 upon each cane push into new shoots, yet relatively few of 

 these will then bear fruit, or at least, large bunches of 

 fruit. As a rule, the better fruit-producing canes on 

 American grapes are developed from side canes (pruned 

 to a bud or two) on a leader which is not less than two 

 years old. 



Peaches and almonds develop fruit on wood which is 

 one year old, and generally the fruit buds are more abun- 



1 For extensive observations on branches, fruit spurs, and other mat- 

 ters of interest in this connection, the student should refer to Bailey'a 

 " Lessons with Plants," pp. l-w. 



