Overgrown holley trees
My new home in northern NJ has gigantically overgrown holley bushes (now trees) 10-12 feet high and wide. I can barely navigate through the front yard! They appear to be of several species.
I'd like to trim them but the leaves are on the "outside" of the trees only.
If I trim more than a couple of inches from the end of the branches the tree will consist of branches with no leaves!
How much can I trim from these behemoths without killing them?
You are better off limbing it up than "trimming" the branches back. That would be called "heading" which 1) on holly's, won't convince it to break bud and leaf out where it already doesn't have leaves and 2) will cause you to actually have More growth at the tips - something you don't want in your path.
If you limb up be sure not to leave stubs - the plant has a hard time growing around them.