SHADE TREES. 



spring before growth begins, or from the middle of February to 

 the middle of April. Sap-running trees are best pruned from 

 the middle of May to the middle of June. In case fall pruning 

 is preferred, trees that run 

 sap should be finished be- 

 fore the middle of October 

 and other trees after this 

 time. Injured or dead limbs 

 should be removed when 

 observed. The latter are 

 best seen before the leaves 

 fall. Dead branches are un- 

 sightly and dangerous to 

 passers-by and to children 

 playing beneath them, while 

 they also endanger the life 

 of the tree by carrying decay 

 into its trunk. A hollow 

 trunk often has its begin- 

 ning in a neglected dead 

 branch. Dead branches also 

 absorb sap and afford breed- 

 ing places for injurious in- 

 sects and fungi. 



Pruning is the removal of 

 some branches and the 

 shortening of others. The 



smaller the branches when cut, the better it is for the tree. While 

 in the nursery, branches are best removed in the bud stage and 

 best shortened by having their tips pinched off. If disbudding 

 and pinching is carefully attended to, the work of pruning in 

 after years is greatly lessened, while the form and vitality of the 

 tree is greatly improved. 



When trees are planted from the nursery with a full height of 

 stem and with the top already formed, it is necessary only to 

 preserve this form by encouraging the leader and checking the 

 growth of ambitious side branches by cutting their tips. When 

 trees with low stems and unformed tops are planted, the stem 



FIG. 21. Sugar maple on South Hill, 

 Ithaca. A hollow trunk often has 

 its beginning in a neglected, dead 

 branch. 



