What can I put in a tree to fill a small cavity?

[Kneejerk Bombas]

Looks like they carved the center out with a chainsaw and painted her up.
You don't happen to have a shot of the crown, do ya?

 

[Guy Meilleur]

Originally posted by Mike Maas
Looks like they carved the center out with a chainsaw and painted her up.

Right, looks like pics Grigory sent from Moscow once. Chilling--how many boundaries broken? Mike, do you see any harm in using an airspade to excavate?

 

[Kneejerk Bombas]

No.
A guy could even make a flexable end to work with to make it easier to get in there. It's a lot of machinery and work to clean out a hole, unless you're there anyway.