AS the lower branches of the trees will cause a more rapid 

 growth in trunk diameter, these branches should be 

 pruned from shade and street trees at intervals of a 

 year or more, as they interfere with street traffic, until a clean 

 stem of ten or twelve feet is reached. Lawn trees require lit- 

 tle attention since low branching, and unsymmetrical form give 

 them character. If possible, trees should be left with single 

 leaders, since crotches are likely to split in later years. If 

 two or more main stems develop, leave the central stem and 

 severely trim or entirely remove the others. When it is nec- 

 essary to restrict the spread of trees within certain bounds on 

 narrow streets and roadways, the ends of the branches should 

 be shortened so as to develop a compact symmetrical crown. 

 Any time after midsummer is suitable for pruning. Shaping 

 can best be done while the foliage is on the tree. Heavy prun- 

 ing is better done in fall or winter. 



Old, neglected trees should first have all dead and imperfect 

 limbs removed. Thin out dense tops by leaving main limbs 

 and the branches immediately radiating from them and limit 

 cutting to the third and fourth divisions in branches. As far 

 as possible preserve the character and natural shape of the 

 tree, making the finished tree look as if no limbs had been 

 removed. Start pruning at the top of the tree and work down- 

 ward. All cuts should be made smooth, close to the base of 

 a limb, and parallel to the axis of the stem. At all times 

 avoid unnecessary wounds by cutting or tearing the bark in 

 making the necessary cuts and in climbing the trees. The 

 surface of scars should be smoothed and painted with a mix- 

 ture of two parts coal tar to one of creosote. It is safer to 

 follow this with a heavy coat of coal tar (the kind used for 

 roofing is best). Large scars should be recoated every few 

 years. 



Control of insects and fungus disease. Leaf-eating insects 

 can usually be killed by spraying the foliage with a solution of 



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