Good afternoon Ms. South,

Thank you for reporting your invasive weeds to the Oregon Invasive Species Hotline. It is great to see local landowners like yourself, taking an active role to control invasive weeds on their property.

From your description, it sounds like you have both Himalayan blackberry (Rubus bifrons) as well as the native Trailing blackberry (Rubus ursinus). The native blackberry has the bluish stem that you described and is much less agressive. In general we do not recommend controlling the native blackberry in natural areas, as this is a natural component in these areas.

In regard to the control of Himalayan blackberry, herbicides can be a very effective control method and fall is the ideal time to treat. We have prepared a Himalayan Blackberry Best Management Practices document (http://weedwise.conservationdistrict.org/weeds/himalayan-blackberry-rubus-bifrons) that you can access, for information about how best control blackberry on your property.

Please take a look at the document and feel free to contact me if you have any additional questions.

In regard to the area near the water, you will want to make sure that any product you use is labeled for use in or near streams. You will also want to be very careful to avoid any spray drift in the water column to protect water quality.

Please make sure to read and follow the label at all times and if any information provided here does not conform with the label, the label takes precedence.

Once again thank you for contacting the Oregon Invasive Species Hotline, and for working to actively control weeds on your property.

Sincerely,

Samuel Leininger
WeedWise Program Manager
Clackamas Soil & Water Conservation District
221 Molalla Ave. Suite 102
Oregon City, OR 97045
503-210-6006
sleininger@conservationdistrict.org

Samuel Leininger
Oct. 5, 2016, 9:34 a.m.