About Invasive Plants
Invasive plants impact everyone!
Invasive plants are non-native plants that have been introduced to BC that have detrimental economic, environmental and health effects on humans, livestock and wildlife. Also known as noxious weeds, or alien species, they are far more aggressive than other common garden or lawn weeds. Economic impacts of invasive plants include reduced forage quality and quantity for cattle ranchers, as many invasive plants are unpalatable to livestock. Invasive plants are the second largest threat to biodiversity in the world, due to their ability to out-compete native plants; this threatens habitat for wildlife as native plants are displaced. Common invasive plants in our region include spotted knapweed, diffuse knapweed, oxeye daisy and orange hawkweed. Recent invaders include field scabious, sulphur cinquefoil and marsh plume thistle.
One of the most significant ways that invasive plants are spread is through human activities. Cars and trucks on the highway, all-terrain vehicles and mountain bikes on trail systems, and industrial activities such as logging and gravel extraction can transport and unknowingly disperse weed seeds to new areas. Many invasive plants are garden ornamentals that escape from gardens and invade natural areas.By knowing what species are considered invasive in our region, you can detect new invaders and respond quickly and efficiently. Read below to learn about some of the most unwanted invaders and how to prevent their introduction, establishment and spread by clicking on individual species. If you wish to contribute to invasive plant management efforts in your community, please contact us.
Often, invasive species form complete monocultures in sensitive habitat creating what is called a "biodesert". Most of these plants have very low habitat value (food and/or shelter) for our native species of insects, birds and animals so these native species are displaced from their natural habitat. Monocultures of invasive plants also have impacts on our fish as these riparian species quickly choke out water ways, deplete them of oxygen, make them impassable and shade them out.
What makes invasive plants so successful?
Many of these plants reproduce by seed, rhizomes, plant parts or any combination of these. Some plants have unique abilities to disperse their seeds including shooting, self sowing, floating, and attaching to animals. Invasive pants that produce seed often make seed prolifically, some species having over a million seeds per plant.
Many of these plants can live where native species cannot. Most can thrive in nutrient deficient, acidic conditions. Many invasive plant species also exhibit a tremdous ability to adapt to a number of different types of living conditions.
Invasive plants grow quickly and agressively. It is this quality that helps them to easily outcompete native vegetation. Some species have been noted to grow up to 4 cm per day!