Knotholes

I noticed the other week that there were two knotholes in the dogwood tree in front of the house. I stuck my finger in one and notices what seemed to be loose dirt in the cavity...or was it ground up tree from some insect that had been eating on it? Termites maybe? I decided to look on the internet for a solution. I came across a YouTube video where an arborist was saying that you could fill the hole with urethane expanding foam, the kind to fill cracks around your house. I bought a can to try it out. First, I cleaned out the hole as best I could. That's when I noticed some little white worms in there. I scooped them all out. I think perhaps they were the culprits making the holes bigger. Then I squeezed in some of the foam from the aerosol can. It expands quite a lot and causes a large bulge. Here's how the holes looked a few minutes later.









Kinda kooky, huh? I let the foam cure and set like that overnight. Then the next day I took a handsaw and cut off the big blob evenly across the surface.





Then I took some old brown paint I had in the basement and painted over the top of the foam and blended the edges with the surrounding bark.



It's been a week and it seems to be holding up. I think it looks okay...and it's certainly better than having insects eat away at the trunk from the inside. I think it will help.