I found a rotten oak with a 3 foot cavity hidden behind healthy bark

I was trimming a large oak in Nashville last week and the bark looked totally normal from the ground, but when I climbed up and tapped it, the whole trunk sounded hollow. I opened a small cut and found a cavity over 3 feet deep that could have collapsed on a house during the next storm. How do you guys check for internal decay without drilling into every tree you climb?

3 comments

3 Comments

charlienelson1mo ago

Had a similar thing happen with a big maple in my yard a few years back. I use a rubber mallet to tap along the trunk listening for a hollow thud versus a solid thump, which works pretty well for catching cavities. An arborist buddy of mine also swears by using a long thin drill bit to check suspicious spots without making a big mess, but I've never been that thorough myself. Your mileage may vary, but I'd rather be safe than sorry with trees near structures, especially after that oak you found.

michaelf5129d ago

Honestly, I read something recently about arborists using a simple moisture meter to help spot decay before it gets bad. Seems like wet spots or soft bark can also be a dead giveaway that something's wrong inside. Tapping with a mallet sounds way more practical for a homeowner though, not everyone has a drill bit long enough for a thick trunk. Ngl, your buddy's method is smart if you really want to know for sure.

grant.sam26d ago

Wait, people actually drill into their trees on purpose? That's wild.