Teasel

Invasive: 

Scotch Thistle (Onopordum acanthium) is present within the Sea to Sky. Teasel can be distinguished by its leaves, having the combination of a broad, cup-like base, tapered end and wavy margins.

 

 

 

 

 

 

Teasel is native to Europe and was introduced to the United States in the 1800s to tease wool. It prefers moist, sunny, open sites with rich soils and favours disturbed areas such as roadsides, ditches, waste places, riparian sites, fields and pastures.

Teasel reproduces by seed, developing more than 2000 seeds per plant which can remain viable for up to two years. As a biennial weed, it forms a rosette during its first year, which will bolt and go to seed the following year. Seeds can be dispersed by wind or birds. Humans may also transport and cultivate Teasel as an ornamental plant.

Teasel is not currently found in the Sea to Sky, so PREVENTION is key:

Learn to identify Teasel: use the images presented on this profile page to learn how to identify Teasel.

What to do if you spot it: You can report any Teasel sighting by clicking here.

DO:

• Regularly monitor properties for weed infestations.
• Minimize soil disturbances and promptly revegetate disturbed areas to prevent the growth of Teasel.
• Check wildflower mixes to ensure that they do not contain Teasel.
• Ensure all flowering heads or buds are bagged or covered to prevent spread during transport to designated disposal sites.

DO NOT:

• Unload, park or store equipment or vehicles in infested areas; remove plant material from any equipment, vehicles or clothing used in such areas and wash equipment and vehicles at designated cleaning sites before leaving infested areas.
• Plant Teasel in a garden, no matter how well-contained its enclosure may seem.
• Compost any flowering heads or buds. Instead, dispose of Teasel in the general/household waste stream at the landfill as the seeds will be able to persist the composting process.
• Move soil, gravel, or fill that has been contaminated with Teasel.

Control

Mechanical 

• Mowing is not effective for controlling Teasel as the plant can re-sprout from the root crown.
• To prevent re-sprouting, dig up rosettes and remove as much of the root as possible.
• If stalks have begun to grow, cut only once flowers have formed and remove stalks from the area.

Chemical

• Glyphosate, triclopyr and 2,4-D are very effective on Teasel.
• If possible, apply herbicide in the late fall or early spring so as not to impact desirable native vegetation.
• We recommend that any herbicide application is carried out by a person holding a valid BC Pesticide Applicator Certificate. Before selecting and applying herbicides, you must review and follow herbicide labels and application rates; municipal, regional, provincial and federal laws and regulations; species-specific treatment recommendations, and site-specific goals and objectives.

Biological Control

• There is no biological control available in Canada for this plant.