Tualatin’s Winona Grange Urges Blackberry Eradication
While wild blackberry cobbler can be a summertime treat, certain varieties are a real threat to our landscape and need to be removed before they take over. Winter is a good time when the vines have dropped their leaves and if you are wearing the right gear.
The most common and threatening are thorny Himalayan blackberries often seen along roadsides, streams and vacant areas around Tualatin. Thickets can sometimes reach 15 feet high and 40 feet wide. We can thank birds and other animals for these gifts, but the original source in our region was the famous botanist Luther Burbank who was trading seeds with a collector in India, thus the name Himalaya. He thought he’d found an ideal new crop for the West coast but unfortunately it got out of control and began to overtake other native plants and then spread across North America. Desirable native berry plants, on the other hand, include the Pacific blackberry, trailing blackberry, thimbleberry, salmonberry, and huckleberry.
Never letting the vines get started in the first place is the best strategy for homeowners. If established already, then root removal is the only guarantee for eliminating this noxious perennial. This means digging out the root crown and not leaving even a small piece in the ground to readily resprout. The process begins with cutting down the above-ground canes to get better access to the root ball with a shovel. Thick leather gloves and protective clothing are vital. A less desirable eradication method is herbicides while some landowners have contracted with goat owners to devour the plants which is only a temporary solution.
An excellent resource is the Tualatin Soil and Water Conservation District (see tualatinswcd.org/species/blackberry/ or call 503-334-2288). The website for the District provides descriptions and photos of native and non-native blackberries. Workshops and other resources are also available.