Invasive plants are spreading aggressively across British Columbia
Often mistaken for wildflowers, invasive plants are spreading through our natural ecosystems, urban landscapes, and agricultural lands at an alarming rate. Invasive plants are spread through several key pathways of invasion including increased international, national, and regional travel and trade; horticulture, gardening, and ornamentals; transportation and utility corridors; seed mixtures (re-revegetation, birdseed, wildflower); recreation; and wildlife, livestock, humans, and pets.
What defines an invasive plant?
The Invasive Plant Council of BC defines the term "invasive plant" as any invasive alien plant species that has the potential to pose undesirable or detrimental impacts on humans, animals or ecosystems. Invasive plants have the capacity to establish quickly and easily on both disturbed and un-disturbed sites, and can cause widespread negative economic, social, and environmental impacts. Many invasive plants have been introduced to British Columbia without their natural predators and pathogens that would otherwise keep their populations in check in their countries of origin. For this reason, invasive plants also commonly referred to as "alien", "non-native", "exotic" or "introduced" plant species.
Why are these plants such a threat?
Second to habitat loss, invasive species have been identified as the most significant threat to biodiversity. In 2000 (updated in 2004), the World Conservation Union collaboratively published a booklet identifying 100 of the World's Worst Invasive Alien Species, four of which currently exist in British Columbia.
| Gorse (Ulex europaeus)  | Japanese knotweed (Fallopia japonica)  | Leafy Spurge (Euphorbia esula)  | Purple Loosestrife (Lythrum salicaria)  |
Invasive plants are more than simply "plants out of place"; these invaders are far-reaching in their impacts, permanently altering landscapes and ecosystem functions and costing economies millions of dollars each year.
Invasive plants affect us all!
Impacts associated with the introduction and spread of invasive plants are not unique to one industry, organization, or community – all citizens, regions, and industries in BC are affected. These unwanted invaders can negatively impact: rangelands by reducing forage quality and quantity; forestry operations by competing with seedlings for light, nutrients, and water; recreation opportunities by puncturing tires, obstructing trails, and reducing aesthetics; and water quality and quantity by increased erosion and sedimentation.
As native plant communities are replaced by invasive plant infestations, biodiversity declines and habitats change. These impacts are often irreversible and restoration can be extremely difficult, if not impossible; therefore, preventing their establishment and spread is key!
The first step in managing invasive plants is recognizing them.
By knowing what species are considered invasive in your region, you can detect new invaders and respond quickly and efficiently. Follow these links to learn about some of British Columbia's most unwanted invaders and how to prevent their introduction, establishment, and spread. If you wish to contribute to invasive plant management efforts in your community, contact a regional invasive plant committee coordinator.
