FILLING TREE CAVITIES 



J. J. Levison 

 (With Plate 6, Containing Four Figures) 



Everyone recognizes the necessity of filling a decayed cavity in 

 a tooth. Everyone knows that the decayed material in the cavity 

 must be removed in order to prevent the destruction of the whole 

 tooth and that the opening must then be filled in order to keep 

 out the further accumulation of injurious substances. Still, there 

 are some who might be surprised to hear of scientific tree 

 " dentistry," or tree filling, although the underlying principles and 

 necessity for such treatment are alike in both human beings and 

 trees. 



Cavities in trees are common even in some of the best kept 

 gardens and will always follow the unskilled pruner or the 

 neglected wound. The cavity in itself is not important unless it 

 be a large one, but it is the breeding place which it affords for 

 enemies such as insects and fungi that is highly important and 

 worthy of the most serious consideration in the care of trees. 

 The accumulation of moisture and the exclusion of light and cold 

 which are characteristic of every cavity are the ideal conditions 

 which the spore of a fungus disease seeks. The spores are pro- 

 duced by the millions on all trees attacked by fungi and it is 

 therefore not the least surprising to find that every tree cavity is 

 dangerously exposed to the attacks of fungi and that when a 

 fungus spore does settle in one of these cavities it germinates 

 rapidly under the favorable conditions of food, water, air and 

 warmth, and soon produces a mass of fibers which penetrate the 

 body of the tree. The weakened vitality of the tree, together 

 with the open cavities, will then invite the entrance of many 

 injurious insect pests, so that within a comparatively short time 

 the death of the tree will become inevitable. 



A timely cleaning and filling of the cavity, however, would 

 exclude the conditions necessary to the development of disease 



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