The former owner underplanted a row of dogwood trees with burning bushes, a scheme that may have made sense when new. But they don't get enough sun to ever turn red and need to be pruned drastically to reveal the dogwoods so I've had enough of them. What is the best way to get rid of them? Can I cut them flush to the ground and apply glyophosphate to the cut? Or simply continue to cut all sprouts? They would be awful to dig up and I'd fear damaging the trees, the geranium macrorhizum ground cover and bulbs.