THE CARE OF STREET-TREES 115 



at the top of the tree, be continued in a downward direction, 

 and completed at the bottom. It is easier to shape the tree 

 by that method, and time is saved in clearing the tree of the 

 pruned limbs. Frequently a limb gets caught in its fall; 

 but as the man works downward he is able to free the limbs 

 and do the cutting at the same time. All cuts should be 

 made close to the base of a limb, and the plane of the scar 

 should be nearly parallel to the axis of the trunk. How to 

 make the cut to prevent splitting and to insure the healing 

 of the scar are the important points in the pruning of all 

 trees. 



Origin of Branch. — A branch of a tree originates from a 

 lateral bud of the main stem. The first year's growth of 

 the shoot from the bud is similar to the first year's growth 

 of the seedling from the seed. As the growth continues and 

 the annual layers of wood are deposited on the main stem, 

 the draft of the sap of the lateral shoot causes these layers 

 to continue up and around the limb. If one were to stand 

 and hold his arms up, the garments around his body would 

 represent the successive annual layers of wood on the tree- 

 trunk, and the sleeves of these garments around the arms 

 would represent the continuation of these layers around the 

 limbs of the trees. 



The Wrong Way. — In Plate 26, Fig. 1, is shown the trunk 

 of a tree with a limb that is to be removed. Frequently such 

 work is done by making a cut the shortest way across the 

 limb, line AB, Plate 26, Fig. 1, and the result is that a stub 

 is left, similar to that shown in Plate 26, Fig. 2. When the 

 limb is so removed, let us see what will happen. There 

 being no draft of sap into the stub, because the end is 

 removed, the next annual layer of wood of the main trunk 

 will not be continued up around the limb, but will end at 



