Invasive trees thrive on man's attack. Pulling the tree or mulching the stumps simply aggravate the root system and it flourishes because it no longer has to feed a standing tree. Honey Locust are a good example of this. They go crazy!!!
Treating the stumps after cutting is a solution. For a multitude of small trees scattered over 5 acres will require a LOT of time. And the treatment needs to applied the moment you cut the tree. For small trees, 3-4 inches in diameter, I've drilled a 3/8" hole into the base of the standing trunk and squirt it full of chemical. Let the live tree suck the chemical down into the root system and kill it.
I'm absolutely not a fan of a tree shear. All they do is create a disaster. Especially if clearing 4-8" trees. Cedar stumps will last a decade or more before they finally rot away.
For spraying chemicals on a standing tree, "Remedy" works the best for me. You can gain some effectiveness if you mix in some 2-4-D. And that mixture won't kill your grasses. Some people recommend mixing with Diesel Fuel but that tries to kill everything it contacts. I also discovered from my friend last year that Remedy will kill lespedeza.
For stump treatment I use Tordon RTU. I also have some pelleted Tordon but rarely use it. Excuse my faded Tordon bottle, it rode in the chain box most of last Summer.
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