I've done that with piranha teeth on the bucket...if there are rocks I like using the root rake grapple better, then removing material with the bucket.Of course if the road is short enough and you have room enough to access it sideways, you can clean it out about 6’ at a time with the front loader. Sounds slow, but it’s actually pretty quick.
Honestly a tractor isn't the best tool, a mini-ex is (generally speaking). Maintaining a road is different, but cutting a ditch is likely best with a mini-ex [with rubber tracks and a] narrow, toothed bucket, and then cleaned up with a wide material bucket. For trees there's a tree shear and root tooth (and thumb) for the big ones. For boulders you might want a hammer. Mind you I'm not a ditch guy and am only in the planning stages of getting a mini-ex, but from the work I've done a tractor isn't usually the best at excavating.