Date: May 1, 2008
Community and Government Affairs
City of Lake Forest Park
206-368-5440
News Release
Invasive Weeds: Himalayan Blackberry
Now's the time to pull them out of your yard!
Himalayan Blackberry (Rubus discolor)is a widespread, non-native, invasive plant. It was introduced to our area by Luther Burbank in the 1900’s (according to the Mercer Island web page on the History of Luther Burbank Park). It is now found wherever the land is disturbed. Although many people use the berries for jams and pies, it is an invasive plant. King County has it listed on their 2008 Noxious Weed List “Weeds of Concern.”
Blackberries, like other noxious weeds. are non-native plants that are taking over our garden and natural landscapes. These plants spread quickly into our natural ecosystems threatening our native plant and animal species.
Identification of the non-native Himalayan Blackberries:
- Thick arching canes with large thorns that grow upright
- Main cane stems can reach up to 15 feet tall with trailing side canes reaching up to 40 feet
- Small white to pink flowers
- Round to oblong leaves that are toothed along the margins usually in groups of 5
- Black edible fruit (Birds disperse eliminated seeds into new areas)
Impacts of non-native blackberries
The canes grow faster and more aggressively than native understory plants and inhibit the establishment of Northwest native trees such as Pacific Madrone, Western White Pine, and Douglas Fir.
Potentially blackberries can increases flooding and erosion potential because the plant limits new trees that might otherwise hold the soil.
The thick mess of canes impedes animals’ ability to move through the natural landscape due to the almost impenetrable thickets.
Stream and banks can be completely dominated by these plants.
For more specific information on removing blackberries, ivy and other invasive species: www.greenseattle.org/files/weed-specific-removal
