I've used my poison in a bag successfully in the past. I use a double newspaper bag, pour in some poison, and tie a knot around the bag. It allowed the leaves to absorb it but here I have only roots - no leaves. My method did eliminate the wandering Hummingbird Vine.
The stumps may look huge only because the photo was cropped but they really aren't. There's a small shovel next to them in this shot:
The ground is now so soft from all the digging that I can't take a chance on placing a ladder there to get the berries, many of which had fallen since I found them quite often during this venture. I cut off many sprigs containing berries but I do realize just one berry could mean I'd face this again.
I dug out annuals from the inside of the garden to have greater access but that left the soil in there too soft for a ladder! A tarp on both sides may help harness the berries.