Yep. My go-to product is plain old Roundup, but the concentrate version that is meant to be diluted with water (don't dilute for this situation). Painted on the freshly cut trunks. Trick is to paint it on thick as soon after cutting as you can. Usually gets the job done. There are also more expensive products marketed to kill "woody" brush that are usually meant to be painted on to freshly cut stumps as well. Don't know if they work any better, but they usually cost more.
