Wormwood

Native: 

Biennial Wormwood (Artemisia biennis), which, as its name indicates, lives for 2 years. It is generally taller and greener than Wormwood, and its leaves are pointier.

 

 

 

 

 

 

Non-Native:

Common Mugwort or Common Wormwood (Artemisia vulgaris), which has white flowers and pointy leaf tips. It is also greener than Wormwood.

Wormwood is native to Eurasia and Northern Africa. It was introduced to North America in the early 19th century for medicinal purposes.

Wormwood will survive in both dry and moist soils, but it thrives in poor, dry soils with full sun. It is generally found on dry, open waste areas or overgrazed rangelands, but also along roads and fencerows as well as in pastures.

Wormwood reproduces primarily by seed. It is a prolific seed producer, and seeds can remain viable in the soil for 3 – 4 years. Seedlings can emerge at any point from late spring to early fall. It can also reproduce vegetatively, by cuttings.

Wormwood is a perennial; the above-ground portion of the plant dies back in late fall, but the crown of the plant remains intact and produces buds and new shoots each spring.

Wormwood’s spread is aided by the horticultural industry, as the plant is still sold as a garden ornamental.

Wormwood is currently found in the Pemberton area, but has not yet been found in Squamish or Whistler, so PREVENTION of further spread is key:

Learn to identify Wormwood: use the images presented in this profile page to learn how to identify Wormwood.

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

DO:

• Regularly monitor properties for weed infestations.
• Minimize soil disturbances and use seed mixes with dense, early colonization to re-vegetate exposed soil and resist invasion.
• Check wildflower mixes to ensure that they do not contain Wormwood.
• Ensure all flowering heads or buds are bagged or covered to prevent spread during transport to designated disposal sites.

DO NOT:

• 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.
• Do not plant Wormwood in a garden, no matter how well-contained its enclosure may seem.
• Do not compost any flowering heads or buds. Instead, dispose of Wormwood in the general/household waste stream at the landfill as the seeds will be able to persist the composting process.
• Do not move soil, gravel, or fill that has been contaminated with Wormwood.

Control

Mechanical 

• Hand-pull or dig up individual plants or small patches; make sure all the roots have been removed.
• It is often easier to dig up the roots when the soil is moist.
• Mowing may prevent seed production, as long as it is done prior to seed set and repeated several times throughout the season.

Chemical

• Aminopyralid, clopyralid, dicamba, glyphosate and 2,4-D are effective for controlling Wormwood.
• Best results are obtained by spraying the foliage and stems of actively growing plants when they are at least 30 cm tall.
• Since Wormwood is hairy, the use of a surfactant is essential.
• 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 biocontrol available for this plant.