J.J. Levison, 1909 in the journal Mycologia , 1(2): 77: 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. As recently as 1974, the US Forest Service recommended "shaping the wound into a vertical oval" and applying "commercial tree dressings such as orange shellac or those with an asphalt base." Proper disclosure: the Forest Service has cautioned readers that the advice in "Your Tree's Trouble May Be You!" might be out dated. By the 1990s, "tree dentistry" was