I have a heck of a time fighting Autumn Olive any opening I make. It grows along every fenceline, uncut hayfield and even manages to grow in the understory in all but north facing slopes. If it's not AO it's multifora rose. Occassionally I'll get a tree grow though. I feel like I have to plant something just to get some diversity in the seed bank. You bring up an interesting point about cutting rather than planting though.