134 AMERICAN POMOLOGY. 



Tkimmtng shouM be practiced in the nursery with a de- 

 finite object in view, and not at random ; much less with 

 any expectation of increasing the hight of the trees by 

 trimming them up. The object in pruning nursery trees 

 should be to develop them in every part, to produce a 

 stout stocky sturdy little tree, one that may be turned out 

 upon the bleak prairie, and be able to withstand the 

 blasts. To produce this result, the leaves should never be 

 stripped from the shoots to make them extend their 

 growth, for the sake of making more leaves ; the nursery- 

 man should know the value of leaves, as constituting the 

 great evaporating surface that plays a most important 

 part in causing the ascent of the crude sap, and also in its 

 elaboration after it has been taken up into the organiza- 

 tion of the plant. Leaves should be carefully preserved, 

 and in the trimming, which is necessary, this should be 

 borne in mind. To make vigorous, stocky trees, the side 

 branches should be encouraged rather than pruned off. 

 The tops may sometimes need to be pinched, to force out 

 the laterals, and to encourage their growth ; if two shoots 

 start together as rivals, one of them should be topped or 

 cut back, or twisted and broken, but not cut off at its 

 origin, unless there be plenty of lateral branches or twigs 

 to furnish the tree. When these become too long, they 

 may be spurred-in, either in the fall and winter when cut- 

 ting grafts, or in the summer, during the growing season. 

 Whenever it becomes necessary to trim off any of these 

 laterals, it is best to do it at mid-summer, as the healing 

 of the wounds made at this period is very rapid. Head- 

 ing off the nursery trees is done to force them to branch 

 out uniformly the second year, to form their heads at the 



