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HOW TO TREAT A TREE CAVITY

In most cases, it’s best to do nothing. A tree will seal over a small cavity eventually, and the tree’s new wood is stronger than anything put into the hole. Large cavities may never close, but as long as the tree does not sustain further damage, a basal cavity may not be a problem. A certified arborist can determine if the tree is a safe or if it should be removed. More here: http://www.mortonarb.org/trees-plants/tree-and-plant-advice/horticulture-care/trunk-wounds-and-decay

Hope this is helpful.

Courtesy of NYBG Plant Information Service