For the first time, a concerted effort is underway this summer to eradicate Japanese knotweed from the Lower Sunshine Coast, the executive director of the Coastal Invasive Species Committee (ISC) said this week.
“Based on outreach, the Coastal ISC has been doing in the Sunshine Coast for the past two years, this is the first year we have made any headway and concentrated efforts in the Lower Sunshine Coast,” Rachelle McElroy said on Aug. 20.
McElroy said past efforts had met with resistance from members of the community, who opposed the use of pesticides. As a result, Coastal ISC had been focusing its efforts north of Sechelt and in Powell River.
However, hundreds of knotweed sites exist on the Lower Sunshine Coast, she said.
“The bulk of the infestations are between Roberts Creek Road and Gibsons, and along Lower Road. We have been working with Roberts Creek director Donna Shugar and the Sunshine Coast Regional District, and their support has made a big difference in moving ahead with treatments for this area,” McElroy said. “This year we were met with little resistance and have been able to focus on the worst areas.”
Coastal ISC’s contractor will be working on the Lower Coast for the next two weeks, wrapping up knotweed treatments on public lands for 2013, she said. The group receives funding from Fortis, B.C. Hydro and two provincial ministries —Transportation and Infrastructure and Forests, Lands and Natural Resource Operations.
For eradicating both knotweed and giant hogweed, a registered pesticide is injected into the stem of the plant.
“Basically it’s a needle in the hollow stalk of the plant,” said Gail Wallin, executive director of the Invasive Species Council of BC, the umbrella organization for the province
“Knotweed is a very aggressive plant,” Wallin said. “The roots will go under a four-lane highway and come up the other side. This is a plant that from an infrastructure perspective is a major concern. It’s a very powerful plant.”
A member of the buckwheat family, Japanese knotweed can grow to three metres in height, at a rate of four centimetres a day. Its stems resemble bamboo and its leaves are egg-shaped with pointed tips. Greenish-white flowers bloom in clusters along the stem from August to September.
While both giant hogweed and knotweed are being targeted, McElroy said Coastal ISC’s overall priority for the Sunshine Coast is “definitely knotweed,” because “there’s a lot more knotweed than hogweed.”
In fact, McElroy said, most reports of giant hogweed on the Sunshine Coast are false.
“People often confuse giant hogweed with its native version, cow parsnip,” she said.
If either invasive is found on private land, McElroy said residents are advised to report the discovery online at reportaweedbc.ca or contact Coastal ISC at 250-857-2472 or by email at email@example.com.
Generally, she said, Coastal ISC suggests residents hire a contractor to kill and dispose of the plants. “We strongly discourage residents from doing it themselves, because we don’t want to spread it further.”
McElroy said Coastal ISC has been successful at eliminating 99 per cent of the knotweed on Highway 101 between Madeira Park and Middlepoint Road after two years of treatment.