(Poor Man’s Orchid, Policeman’s Helmet, Indian Balsam, Touch-me-not)
Himalayan Balsam is a prohibited noxious weed. It has the potential to take over native vegetation forming a monoculture and destroying wildlife habitat and waterfowl breeding grounds. They can outcompete cattails, rushes, and sedges in riparian areas and due to shallow roots allow for erosion and destruction of shorelines.
Read more about Himalayan Balsam
Himalayan Balsam is an annual which grows at an impressive rate achieving heights of 1 to 3 meters. It has a hollow bamboo-like stem with prominent ridges. When under stress, it can grow in a spindly grass-like fashion, flowering close to the ground.
The leaves and stem are tinged reddish purple colour with whorls of three leaves twirling up the stem. Leaves are lance shaped and have prominent veins and serrated edges. The flowers can come in a multitude of shades from white to pink to dark purple. Flowers are heavy with nectar and can attract bees away from native species. Seed capsules can contain up to 16 seeds and when they explode, shoot seeds up to 10 meters away. Seeds can stay viable for seven years. An average-sized plant can produce 700-800 seeds in total.
How to control Himalayan Balsam
Hand pulling works best but needs to be done early in the season before seeds form. Disposal by bagging and burning is recommended, but for large patches this doesn’t work. The “pick, break, and drop” method, which involves pulling out the plant, breaking it apart a few inches above the roots, and dropping it on drier land to let it dry out and die, is more effective for larger areas.
After August, tops should be bagged to prevent seed dispersal. Some herbicides are effective, however, sprayed flowering plants can still produce viable seed.