FRUIT-BUD FORMATION 



Relatively increasing carbohydrates 



Relatively increasing nitrogen 



I 

 Nitrogen+(not 



limiting) 

 Carbohydrates — 



(limiting). 



II 



Xitrogen + (not 

 limiting to use 

 of carbohydrates 

 in vegetation) 



Carbohydrates+ 

 (not limiting). 



Ill 



Nitrogen + (lim- 

 iting use of car- 

 bohydrates in 

 vegetation) 



Carbohydrates+ 

 (not limiting). 



(lim- 



IV 

 Nitrogen — 



iting) 

 Carbohydrates -H 



(not limiting). 



Light pruning of 

 natural growth 

 tendencies. 

 N. decreasing 

 through utiliza- 

 tion by tree if 

 not renewed, y 



Lighter pruning, 

 less N. fertilizer. 



Excessive prun- 

 ing, shading of 

 trees. 



Heavy pruning, 



heavy N. ferti- 

 lizer, 

 heavy moisture. , 



No pruning, dry 

 soil, no fertilizer. 



Pruning, N., fav 

 tilization, cul- 

 tivation, etc. 



57. Pruning. — The relation of pruning to fruit-bud for- 

 mation has ah-eady been illustrated in part by the above 

 outline and the subject is treated more fully in Chapter V. 

 Since root-pruning is less frequently practiced than top- 

 pruning, it is l)riefly discussed in this connection. Summer 

 pruning is taken up later (p. 98), but it is sufficient to say at 

 this pomt that summer pinching, particularly on the peach, 

 results in the formation of an increased number of fruit- 

 buds on short spurs. More extensive summer pruning has 

 not proved desirable in eastern United States, but certain 

 types find some limited use under western conditions. 



Root-pruning has long been advocated as a means of 

 causing barren trees to bear fruit. The theory was that, by 

 cutting off a portion of the roots, the intake of water (and 

 unelaborated food materials) and hence the sap flow was 

 reduced, and this brought about a relative preponderance 



