150 MASSACHUSETTS HORTICULTURAL SOCIETY. 



action, especially those that attack the roots Avhen they are 

 wouiuled. It is not my pnrpose, nor would the limited time allow 

 me, to give an account of these special parasites. Enough, how- 

 ever, has been said to demonstrate the danger of open wounds 

 and the necessity of aiding Nature in her efforts to heal them. In 

 the natural course of events many wounds must occur from the 

 violent action of the wind and snow, and we should do what we 

 can to remedy them. But it is perhaps more to the purpose that, 

 recognizing the danger, we should use our influence to prevent the 

 avoidable and wilful maiming of our shade trees by careless and 

 ignorant people. 



As far as the treatment of wounds is concerned, our object 

 should be to coveT the exposed surfaces, so that moisture, which 

 would cause them to rot, may be excluded, and that the spores of 

 fungus parasites may not find an entrance. A useful hint as to 

 to what should be done is given us by nature herself. In some 

 respects the coniferous trees suffer less from wounds than other 

 trees. The reason is that in the wood of conifers there are canals 

 or passages which contain resinous substances, and when the 

 ATOod of such trees is wounded they exude and form a close 

 varnish of resin over the exposed surfaces, Avhich are thus kept 

 dry and protected from weathering. As a result, the wood is less 

 likely to rot than in the case of other trees whose wood contains 

 no resin. In trees of the latter description, when wounds occur 

 b}' accident or design, the indication, to use a medical expression, 

 is to coat the cut surface with tar or some similar substance. 

 There are several practical considerations to be borne in mind in 

 applying the tar. If the wounded surface is rough and splintered, 

 it should in the first place be made as smooth as possible, and 

 where branches have been broken off a few inches from the axis 

 from which they sprung, they should be sawn off close down to 

 the main axis. 



AYhen branches are to be pruned, it is of importance that it 

 should be done at the right season. It might be inferred from 

 what was said previously that the summer months would be the 

 best time, because the cambium is then active and the callus' 

 begins to form at once. There are, however, other points to be 

 considered. Unless the branch is small, it will take several years 

 for the callus to cover the whole wound, and, meanwhile, the 

 exposed wood may rot unless well coated with tar. The important 



