30-year-old blackboard paint stinks.
If you put weight on buddleia trunks, they bend then split (at least if you have three joined at the base in a woodlouse nest). I found 'sitting' on the trunk and bouncing worked well. A novel tree-felling technique, with no prizes for elegance, but I wasn't after one of those.
The root still in the ground awaits another day, as do two holly roots and one bramble root nearby.