Thank you! That's what I've read around here before and why I bought "the stuff." I haven't cut it yet because I wasn't ready to open the package in that much wind. If it keeps trying to grow after the fresh-cut-stump treatment, I could paint the leaves, then cut it a few days later & paint the stump again, then repeat as necessary until it peters out. I'm imagining an oak that has gotten to this size is going to be vigorous as heck. It's grown about 3 feet above the Gardenia since I noticed it barely sticking up from the top. It took me several trips to a store to get up the nerve to actually look at the packages and try to pick one.
Might it be more powerful to lean it over and paint many leaves, then cut & paint stump a few days later? Or I could lean the tip into a jar of 'cide. The last time I did that with a vine, it worked. (No, I have no small children or pets who would get into it, yes I would cover it with plastic to keep rain & wildlife out.)
When I'm @ home and have time to put more info about the specific product sometime this weekend, I would very much appreciate any input on employing it most effectively, in the smallest worthwhile quantity. : + )