56 TREE WOUNDS AND DISEASES 



around the stem cannot well be avoided, and 

 the instances are few, " dishing " should be 

 practised. This consists in forming a saucer- 

 like receptacle with the soil around the tree 

 trunk, and at a distance of, say, six feet from 

 the stem. Sometimes a retaining wall of old 

 bricks is built around the stem, but in most 

 cases it will be found sufficient to gradually 

 slope the soil from the trunk backwards, and 

 thus allow of the proper aeration of the 

 ground. Trees, the roots of which have been 

 covered with soil to such a depth that an un- 

 healthy condition is brought about, quickly 

 fall a prey to root fungus and the attacks of 

 injurious insects. As showing the evil effects 

 of placing earth at too great a depth around a 

 tree stem, the accompanying illustration of an 

 elm trunk is reproduced. First the bark be- 

 came loose and fell off in patches, then diseased 

 wood appeared, and finally the dread fungus 

 Stereum brought about the death of the tree. 



Stagnant moisture is usually readily re- 

 moved, while natural decay and a stag- 

 headed condition may in some cases be at 

 least temporarily dealt with by timely and 



