Invasive Plants What defines an invasive plant?

Invasive Plants Invasive alien plants are brought to Canada, either accidentally or intentionally, and include species like purple loosestrife, Japanese knotweed, and scotch broom, to name just a few. These plants have the ability to establish quickly and are highly competitive due to prolific seed production, deep taproots, or early flowering. Because they arrive in Canada without their natural predators to keep them in balance, they can spread rapidly, forming dense patches over large areas and often displacing native plants. Since animals rarely eat these species, infestations can impact wildlife habitat and rangeland. Invasive plants can have huge economic impacts by competing with desirable agricultural crops and forest plantations. They can also pose significant threats to human health and safety by causing skin irritation or burns and reducing visibility along transportation corridors. 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. For more information, please visit the Coastal Invasive Species Committee website and their brochure: Invasive Plants on Vancouver Island, the Gulf Islands and the Sunshine Coast

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. 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, two of which currently exist on the Sunshine Coast: Gorse (Ulex europaeus) 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.

Knotweed (Chaster Park)

Japanese knotweed

(Fallopia japonica)

English Ivy (Ocean Beach

Esplanade)

Giant Hogweed

(Maple Park)

Periwinkle (Ocean Beach Esplanade) Butterfly Bush

(Roberts Creek)

Disposal of Invasive Plants The Regional District is in the process of developing a strategy for the disposal of invasive plants. Until then, all garden waste (except for Giant Hogweed which must be bagged and sent to the landfill) is to be brought to: Salish Soils, 5800 Black Bear Road (next to Lehigh Construction Aggregates) 604-885-5383 [email protected] Monday to Friday 8am-4:30pm Saturday & Sunday 10am-4pm Fees may apply for loads heavier than 5 tonnes. Please note that knotweed MUST be separated.

Examples of Invasive Plants on the Sunshine Coast!

Knotweed (Chaster Park)

Scotch Broom (Ocean Beach Esplanade)

Scotch broom is often admired as a beautiful ornamental species. With bright yellow flowers and leathery green stems, it is certainly attractive; however, it is considered a highly invasive alien plant. This woody perennial shrub can be identified by its yellow pea-like flowers that bloom in May, and flat brown seed pods Refer to Scotch Broom T.I.P.S. for information on prevention and control methods.

Giant Hogweed (Maple Park)

Giant hogweed is a perennial member of the Parsley or Carrot Family native to Asia. It closely resembles our native plant cow parsnip, except the taller giant hogweed grows up to 6 metres or more. It was first introduced to North America as a garden curiosity. Its tenacious and invasive characteristics have made it a garden pest that can readily escape cultivation. Giant hogweed sap contains toxic chemicals that are harmful. Please review recommendations below for appropriate health and safety measures. Refer to Giant Hogweed T.I.P.S. for information on prevention and control methods.

Knotweed is a tall shrub with bamboo-like stems. It has been planted throughout South and Central Vancouver Island and the Gulf Islands as a garden ornamental but quickly spreads to form dense thickets in a variety of habitats, including dry roadsides and moist stream banks. Small patches can quickly spread into large areas, leaving little room for native species to grow. Refer to Invasive Knotweed T.I.P.S. recommendations for information on prevention and control methods.

Knotweed (Chaster Park)

Butterfly Bush is an attractive shrub which bees and butterflies seem to adore. However, it can alter the proportions of nitrogen and phosphorous in the soil and can compete with juvenile Douglas-fir in forests. The plant can be controlled by hand-pulling small plants but all of the stems and roots must be removed. Larger plants can be cut to the base or dug up. Stumps can be treated with a glyphosate or the stump can be covered with a thick plastic bag or mulch. Remove new sprouts that may appear. If plants cannot be removed, cut off flower stems before seed set. No biocontrol is available in Canada. The seed bearing capabilities of the plant are awesome. A single flower head can produce 40,000 seeds while maintaining a better than 80% germination rate. The seeds remain viable for three to five years; this means great diligence is required to remove the species completely from an area. Interestingly, B. davidii does not compete well in shade. A garden without direct sun can help keep this pest out. It is also most competitive in disturbed, compacted and poor soil. These characteristics make it a prime suspect for stream banks in areas that have increased runoff from new development.

Butterfly Bush

Periwinkle (Ocean Beach Esplanade)

English Ivy (Ocean Beach Esplanade)

Lamiastrum galeobdolon (Yellow archangel)

And others…

English Holly

Before you buy… take some time to learn a bit about the most common invasive plant species in the region and some healthier alternatives. There are several brochures that you might find helpful: Help Stop the Spread of Invasive Plants Grow Me Instead

Acknowledgments Most of this information was provided by the Coastal Invasive SpeciesCommittee.

Reporting Invasive Plants Unusual plants that appear to be taking over or growing out of control should be reported in one of these ways: • Toll Free 1-888-WEEDSBC • Online database, ‘Report-A-Weed,’ Invasive Alien Plant Program (IAPP): www.for.gov.bc.ca/HRA/Plants/raw.htm Please report the following information: 1. Species (or plant characteristics and photos if species is unknown) 2. Size of infestation 3. UTM coordinates or directions to site 4. Your contact information