Filling a tree hole
I've researched enough to know that filling holes with caulk, etc. is not a popular fix any longer. Last week I was able to enjoy the warm weather and checked the trees in my yard. I have a third generation/volunteer sour cherry tree that has produced many pies over the years. 6-7 years ago it was badly damaged in a hail storm; the wounds have mostly healed, but the main trunk runs almost horizontal to the ground and the top of the trunk has a two foot section where the heartwood is exposed. This winter the birds made several deep holes into the exposed wood. Fearing further bird/insect/moisture damage I cleaned out the holes and filled them with cement. Now I'm wondering if the Portland cement mixture will be toxic in the fruit. Any advice is welcome, thank you.
Certified GKH Gardening Expert
Research has shown that filling tree holes does more harm than good. Those holes develop a natural barrier to protect itself, so it isn't necessary to intervene.
This article will give you more information: https://www.gardeningknowhow.com/ornamental/trees/tgen/patching-tree-hole.htm