8 MASS. EXPERIMENT STATION BULLETIN J 97 



Root Injuries. The most conspicuous root injuries are those resulting from 

 excessive root pruning; especially the type shown in figure 7, upper. The almost 

 certain sequel to such pruning is shown in figure 7, lower. 



Neglected Pruning. Most trees require a minimum of pruning for health, 

 appearance, disease control, safety, utility line clearance, or other considerations. 

 Delay in pruning or failure to prune correctly may prove to be a costly mistake, 

 especially in municipal shade tree management. Severe damage to neglected 

 trees, injury to citizens or their property, as well as the interruption of the service 

 of wire-using agencies, may result. 



Branch Stubs. Careless pruning or storm injuries sometimes leave jagged 

 branch stubs as an invitation to wood-destroying fungi. Probably tree deteriora- 

 tion starts in this way more often than in any other. 



Exposed Wounds and Cuts. Many tree casualties are found to result from un- 

 treated wounds and cuts. Prompt treatment of wound: and immediate attention 

 to cut surfaces following the removal of branches are constructive preventives 

 useful in checking early deterioration. 



Cavities. Extensive cavities in trees represent the advanced stages of pro- 

 gressive decay following injuries. The best treatment for them is to prevent their 

 occurrence, or check their progress. 



Dangerous Trees. Trees seriously weakened by disease or decay at a large 

 crotch (Fig. 2), and skeleton trees which have ceased to serve communities for 

 purposes of shade not only are frequently a blot on the landscape but may actually 

 constitute a serious menace. Sometimes failure to appreciate the need for the 

 prompt removal of such trees or the lack of responsibility for this work may cause 

 serious delay in the removal of a dangerous tree. The result of this delay may 

 prove injurious, fatal, or costly to someone. 



Evergreen Failures. Coniferous evergreens may be injured by the weight of 

 snow on branches or tree tops. When parts of trees are broken, the same treat- 

 ment accorded wounds of deciduous trees may be given or may be altered as 

 necessary. In all cases, branch stubs or rough jagged edges of wounds should be 

 cut back smoothly. The resin coating which usually covers cut surface b of 

 evergreens suffices as a dressing. When trees are broken during a wind or wind- 

 and-rain storm, the entire tree or most of it commonly falls (Fig. 1). The guj-- 

 ing of evergreens in certain locations will sometimes prevent accidents of this 

 type. 



Trees and Utility Wires. Trees and wires both serve society in war as in 

 peace. Adequate tree maintenance and maximum service from wire-using agen- 

 cies ,do not represent fundamentally divergent policies. Certain conflicts between 

 trees and wires are inevitable, however, and the results of some of these conflict? 

 and the mechanical devices adapted to overcome or minimize them are shown in 

 figure 8. Shade tree maintenance has benefited materially from the joint use 

 of poles by uulities, as well as in other progressive utility programs. The almost 

 forgotten overhead w're mazes (Fig. 9) which have been compacted (Fig. 10) 

 and in many cases placed underground, foretell even better conditions for ."^hade 

 trees in the future. Placing utility wires underground, however, should not be 

 considered a panacea. In certain instances this practice is desirable and practical, 

 but at other times the cost to consumers would be prohibitive. Nor should it be 



