I've bred a number of Forestry trees, set them up in a planter/harvester and found that the harvester refuses to chop them down.
After some messing around I figured out the harvester only refuses to harvest bred trees.
The planter seems to work fine, so that's nice 😄

I am using the Direwolf20 1.1.1 version

MFR now has a config option to attempt to auto-recognize some things it can harvest, which should cover most/all logs and leaves.

This appears to be trees from a forestry addon that aren't getting harvested.