Invasive Plants, Pacific Northwest
Himalayan Balsam has flowers that resemble an english policeman’s helmet (one of its common names). It is native to the western Himalaya and was brought to Canada in the early 1900’s as an ornamental garden plant. This plant is swiftly spreading through the watercourses and along logging roads all over coast and is a real problem on Vancouver Island.
The plant does produce rhizomes. This plant also produces up to 2000 seeds from each plant. Himalayan balsam is shade tolerant. It is also quite common in private gardens where it often invades to such an extent that it becomes a real nuisance instead of a garden beauty.
Driving along the logging roads, you can see it growing along side the road where it looks quite pretty, but this plant is a real problem. It can grow to 3 meters tall and spread its seeds for up to 10 kilometers before they take root.
Himalayan balsam primarily spreads its seeds by using waterways. So you have to go after the plant at its furthest upstream population first and then work down the stream thus stopping new populations from getting started. The plants that grow along the logging road must be pulled up and destroyed before their seed becomes mature.
Make sure to properly discard all plant pieces in thick plastic bags and transport them to a sanitary landfill site or incinerator. Do not compost.