Invasive Species

Our local environment is beautiful but vulnerable:

  • Biodiversity: After habitat loss, invasive species are the #2 threat to biodiversity.
  • Wildfire Risk: Weeds like Scotch broom are highly flammable, rapidly increasing fire danger in open areas and along roadsides.
  • Climate Resilience: Invasives smother the deep-rooted native plants that protect our soil and manage water during extreme weather.

Species of Concern

  • Scotch broom: Bright yellow flowers, highly aggressive, and a major fire hazard. Action: Cut at ground level in the spring. Join our May “Broom Busting” events.
  • English ivy: Heavy vines that climb and eventually kill native trees. Action: Snip vines at the base of tree trunks. Watch for “Ivy League” cleanups at Cooper’s Green.
  • Giant hogweed: Tall plants with large, white umbrella-like flowers. Action: Do not touch. The sap causes severe skin burns. Report sightings immediately.
  • Pumpkinseed fish: Illegally introduced to Trout Lake, severely altering the local biology. Action: Never release aquarium fish or aquatic pets into local waters.

Scotch Broom

Scotch broom is difficult to control once It has established on a site due to the massive production of seeds that are spread in the area. For mature and dense infestations of Scotch broom, aggressive control methods are required. The Halfmoon Bay Broom Busters organize work groups to mechanically remove Scotch broom.

Cut at Ground Level & Go After the Pioneers. You need to find the single stem of each plant. Find the main stem or trunk that goes into the ground and cut at ground level.

Scotch broom is most vulnerable when in bloom, because the energy of the plant is above ground in the flowers. If cut at ground level while in bloom plants typically die in the heat of summer. You do not need to remove the roots unless cutting at wet times of year. Learn more about controlling Scotch broom.

English Ivy

Another import to the coast, often discarded when hanging baskets are finished blooming, English ivy thrives in the rainforest climate, and is frequently seen climbing Cedars and Douglas-firs and swamping lower-growing plants.

As the gardeners in Stanley Park know well, English ivy can infest forest giants and bring them down. Battalions of volunteer Ivy Busters have spent seasons eradicating ivy from Vancouver’s landmark tourist attraction. The lagoon at Coopers Green Park demonstrates the destruction that English ivy can do to native species and has been a focus of volunteer efforts.

Knotweed (Japanese, Himalayan, Bohemian and Giant)

Japanese knotweed is found across the Sunshine Coast. In 2016 the Halfmoon Bay Environmental Society held a public forum to alert and educate residents of the Sunshine Coast about the threats posed by Japanese knotweed. In the UK and Europe, Japanese knotweed has become a huge economic problem, destroying property values and home equity. Under the B.C. Noxious Weed Act property owners are legally required to remove knotweed on their land.

To report knotweeds on the Sunshine Coast go to reportaweedbc.ca. The B.C. Ministry of Transportation and Transit, and other land managers such as B.C. Ferries, actively respond to reports.

Originally imported as an attractive bamboo-like ornamental, Knotweed spreads rapidly, sending roots down three metres capable of penetrating asphalt and concrete foundations. It crowds out everything else, can reproduce itself from small fragments, so it is dangerous to compost and very difficult to kill. Homeowners Guide to Knotweeds.

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