Thank you for your report, and apologies that you did not receive a timely reply. There are many methods for controlling blackberries. Cutting and digging can be possible for small patches, but larger ones may require chemical treatment. Most times repeat treatments are needed regardless of your method as they are tenacious. Lots of good ideas at https://kingcounty.gov/services/environment/animals-and-plants/noxious-weeds/weed-identification/blackberry.aspx. You can also contact the East Multnomah SWCD for guidance, https://emswcd.org/. Best, Lindsey

Lindsey Wise
May 17, 2021, 8:09 a.m.