PRUNING— THE AMOUNT OR SEVERITY 



417 



wood and in this way concentrating the energies of the tree upon a better 

 support of what is left. The lower line shown in Fig. 49 gives graphically 

 some idea of the manner in which the amount of pruning should vary with 

 age in the average apple, pear, plum or cherry tree which is rather slow 

 growing at first and bears principally on spurs. Of course as the trees 

 vary in vigor, rapidity of growth, fruiting habits and in other respects 

 there should be accompanying changes in the severity of the annual 

 pruning. Thus the peach ordinarily begins bearing at an earlier age 

 than the apple or cherry. Consequently it should be pruned to leave 

 fruiting wood and permit bearing earlier. Furthermore, since it bears 

 fruit only on shoots of the preceding year, regular production depends 

 on annual provision for a good supply of new shoots. If these are to be 

 produced on the lower part of the tree where the weight of the fruit will 

 not place an excessively severe strain upon the crotches comparatively 

 heavy annual pruning is necessary. At no stage in the life of the peach 





Age 



Fig. 49. — Graphs showing relative amounts of pruning required for the peach and apple at 



different ages. 



tree is it necessary practically to discontinue pruning in order to develop 

 fruiting wood and bring it into bearing. The upper line in Fig. 49 

 shows roughly how the amount of pruning desirable for trees of this kind 

 varies with age. Similarly it is possible to draw graphs for the amounts 

 of pruning required by trees of other kinds. It should be emphasized, 

 however, that these will vary in details not only with different kinds of 

 fruits, but with varieties of the same kind and for the same variety 

 from place to place and under varying soil and environmental conditions. 

 Summary. — By and large, unpruned trees increase in size more rapidly 

 than pruned trees of the same kinds and the dwarfing effect of pruning 

 is more or less directly proportional to its severity. This dwarfing 

 effect is a result not so much of the production of less new shoot growth 

 each year as of the amounts of wood removed. The dwarfing effect 

 of top pruning extends to the root system because of the reduction in 

 total leaf area. Pruning generally results also in a diminution in 



