Five years ago there was no policeman’s helmet (Impatiens glandulifera) along the Necanicum River or its tributary creeks, as far as anyone knows. Now this pretty but highly invasive weed can be seen throughout the Necanicum watershed, choking out native plants and reducing plant and animal diversity while increasing the risk of streambank erosion. The plant’s seed pods can eject seeds up to 20 feet. Those seeds float, spreading the plant downstream year to year.
In response, North Coast Land Conservancy and the Necanicum Watershed Council have launched a three-year project to rid the Necanicum watershed of this invader. Four summer stewardship interns will be pulling out policeman’s helmet in the upper reaches of the watershed in June and July, while it is in bloom and easy to spot (but before the seed pods have matured). Volunteer kayakers are surveying the river for patches of policeman’s helmet and logging locations with their smartphones. Riverside property owners are being contacted and urged to be vigilant about the plant’s occurrence on their land. Meanwhile NCLC staff and volunteers will be working downstream at NCLC’s Circle Creek Habitat Reserve to eliminate policeman’s helmet there. An $86,000 grant from Oregon Watershed Enhancement Board is helping to fund the three-year effort.
Public engagement will be key to getting rid of this weed. Wherever you live in Clatsop or Tillamook counties, keep an eye out for policeman’s helmet on your property. If you see it, pull it (it uproots easily), make a pile of the plants, and stomp on them to crush the stems. Visit NCLCtrust.org/pull-pile-stomp for more details and to report any sightings of the plant.
It’s easy (and satisfying) to pull this weed, which grows 3 to 6 feet tall. NCLC is recruiting volunteers to join their “Weed Warrior Wednesdays” crew—just once, or every week—working at Circle Creek throughout June and July. A Saturday stewardship day is also planned for July 8. Details are at NCLCtrust.org/pull-pile-stomp.
Policeman’s helmet is named for the shape of the blossom, which resembles an old-fashioned British policeman’s headwear. It is native to the Himalayas and was introduced in North America as an ornamental garden plant but has since spread widely. It was first seen along the Necanicum River and its tributaries in 2013.