Local Governments Join Forces to Bust Invasive Plants

May 18, 2016

The BC provincial government has declared May as invasive species action month, and local governments in the Comox Valley have once again joined forces to bust invasive knotweed – and new for 2016 - giant hogweed.  Both plants are considered alien invasive species in BC and if left unchecked can wreak havoc on our local ecosystems and diminish property values. And in the case of giant hogweed, can lead to third degree burns when in contact with skin, due to its clear phototoxic sap.

This successful regional program, first launched in 2013, includes all four local governments, the Town of Comox, City of Courtenay, Village of Cumberland and the Comox Valley Regional District (CVRD), in partnership with ‘Alien busting’ the Coastal Invasive Species Committee (Coastal ISC). The goals of the program are to verify all knotweed and giant hogweed reports within these jurisdictions to provide professionals to conduct treatments on select sites.

The 2015 program targeted 58 knotweed sites eradicating seven completely and significantly reducing infested areas by 75%. These sites are now recorded in the provincial invasive alien plant program database for tracking and follow-up monitoring and treatment. Effective control usually takes three to five years.

WANTED: Knotweed for: Extensive damage to private and public property and wreaking havoc on the environment. Notes: Spreads by roots, seeds and plant fragments. (see photo below)

Knotweed is considered one of the world's worst invaders. It is a hollow stem shrub, native to Asia that resembles bamboo. It can grow up to 4 centimetres a day and causes serious damage to foundations, driveways, and septic system, as well as natural to habitats. In the UK, Japanese knotweed has spread rampantly and now homeowners cannot secure mortgages or insurance on properties with knotweed. Cutting, mowing, and pulling can stimulate shoot growth and may cause roots to spread further, resulting in new infestations up to 20 metres away. As well, knotweed has the ability to regenerate from a very small root or stem fragment and can remain dormant for many years.

WANTED: giant hogweed for: Stem hairs and leaves contain a clear, highly toxic sap that, when in contact with the skin, can cause burns, blisters and scarring. Notes: WorkSafe BC has issued a Toxic Plant Warning for Giant hogweed. (see photo below)

Giant hogweed is an herbaceous perennial. Stems are hollow, ridged, green with purple spots to purple-red and may have stiff hairs present.  When in flower, plants can grow to 6 metres tall.  Flowers are small, white and clustered in large umbrella-shaped heads and leaves are green and deeply incised (almost to leaf vein) and have three segments.  Leaves can exceed 2.5 metres in length.

Local residents in CVRD’s electoral areas can benefit from subsidized treatments by select spot application this summer, while treatments in Comox, Courtenay and Cumberland will focus on public lands.

Coastal ISC appreciates the cooperation of all residents in addressing knotweed and giant hogweed.  Reporting knotweed and giant hogweed is very important in controlling these priority invasive plants in the region.  The Coastal Invasive Species Committee is asking the public to report sightings of knotweed and Giant Hogweed until the end of May by email info@coastalisc.com or calling 250-871-5117 in the Comox Valley; toll free on Vancouver Island 1-844-298-2532.

"Knotweed - wanted for causing a huge headache across British Columbia, but with the public’s help we can prevent it from taking over our coastal communities. It's an invasive and aggressive plant that spreads easily and can impact property values, the environment, and can cause safety issues on roadways. This regional program will save considerable taxpayer dollars. Visit Knotonmyproperty.com, or pick up a booklet from your local government to learn how to defend your property from invasion” explains Rachelle McElroy, Executive Director of the Coastal ISC.

“The spread of knotweed has negative ecological and economic impacts and Giant Hogweed has serious health impacts. We are pleased to work with our local governments region-wide to combat invasive species in our area,” said Edwin Grieve, chair of the Comox Valley Regional District electoral area services committee.

“Once again we're very pleased to be working in partnership with other local governments and our residents to help fight invasive species in our community. It's truly a collective effort. Taking these steps now is vital to protecting our natural ecosystems for future generations," added Mayor of Courtenay, Larry Jangula.

A knotweed and giant hogweed alert sheet, providing information on identification, proper disposal, and reporting options has been developed and is available on the CVRD website at www.comoxvalleyrd.ca/invasiveplants. For more information on identification, common look-a-likes of these plants and its damaging impacts, as well as other invasive species that are being managed in your area please visit the Coastal Invasive Species Committee website and click on the "Invasive Species" tab.


Media contacts:

Rachelle McElroy, Executive Director, Coastal Invasive Species Committee. Email: rachelle@coastalisc.com , Phone: 250-871-5117


Doug DeMarzo, Manager of Parks, Comox Valley Regional District.  Email ddemarzo@comoxvalleyrd.ca, Phone: 250-334-6053


Nancy Gothard, Environmental Planner, City of Courtenay. Email nhofer@courtenay.ca Phone: 250-334-4441


Kevin McPhedran, Parks and Outdoor Recreation Coordinator. Village of Cumberland.  Email: kmcphedran@cumberland.ca Phone: 250-336-2291


Allan Fraser, Parks Superintendent, Town of Comox.  Email: afraser@comox.ca  Phone: (250) 339-2421