Reading Time: 2 minutes Often found in high densities across Alberta, perennial sow thistle seems to be a noxious weed that doesn’t quit. Not only does this pest cause significant yield loss in many crops, but it’s a host for several plant pests that attack economically important crops such as alfalfa, winter wheat and canola — just to name […] Read more

Perennial sow thistle costs farmers across Alberta
Noxious Weeds: Perennial sow thistle causes yield loss and acts as a host for pests

Devil’s trumpet is a potentially deadly invader
Noxious Weeds: Jimsonweed
Reading Time: < 1 minute Although its exact origin is unknown, devil’s trumpet — otherwise known as jimsonweed — is found in many countries around the world in both agricultural and ornamental settings. Introduced to this province as a contaminant of agricultural seed, this smelly weed is under review by the provincial Agriculture Ministry and it has been recommended to […] Read more

Another invader from the buttercup family
Cultivation is not successful and no chemicals are registered for control
Reading Time: < 1 minute Yellow clematis, a perennial vine related to the buttercup family, can become quite invasive if proper precautions are not taken. In Alberta, it has been designated as noxious for this reason. Often purchased, however, from gardening stores as a bedding plant, this weed can spread by wind which can take the seeds far beyond the […] Read more

A weed that prospers on degraded pasture
Noxious Weeds: Hoary alyssum
Reading Time: 2 minutes Thought to be brought to North America as a seed contaminant from Europe, hoary alyssum is toxic to horses and other livestock. It has a variety of life cycles depending on site and weather conditions, which makes this weed tricky to control. A prohibited noxious weed in Alberta, this pest can be easily identified. Hoary […] Read more

Keep watch for this potential new invader
Noxious Weeds: Puncturevine
Reading Time: < 1 minute So far uncommon to Alberta, puncturevine has all the makings of a potential headache to you and me, alike. What started as an annual herb in southern Europe has started spreading into Canada (in British Columbia and Ontario). Like most other weeds, this plant prefers areas of disturbed, bare ground and grows as a summer […] Read more

This quick-spreading weed gets an early start
Noxious weeds: Canada thistle
Reading Time: < 1 minute Spring brings lovely native flowers, but also noxious weeds. The aggressive perennial Canada thistle is a favourite of disturbed soils of all types. It starts sending shoots from horizontal roots to the surface of soil around mid-April, with flowers to follow in mid-June and continuing throughout the summer. Easy to distinguish from other weeds, this […] Read more

Don’t be fooled by this weed’s pretty flower
Noxious weeds: Field scabious
Reading Time: < 1 minute Field scabious was introduced as an ornamental from Europe and is now taking over roadsides and pastures. It can be found throughout central Alberta and has the ability to invade even undisturbed plant communities, such as hayfields. Once established it is very difficult to control. Flowers can be a purple- to blue-coloured clustered head, resembling […] Read more

You won’t raise a glass to this invasive weed
Noxious Weeds: Absinthe wormwood
Reading Time: < 1 minute A tough, semi-woody perennial plant native to Europe and Asia, absinthe wormwood typically grows in stems and forms in a clumping habit. The most distinguishing feature of the plant is its finely divided leaves combined with a silvery-grey colour. Absinthe wormwood also has a very strong and distinct odour which is very similar to sage. […] Read more

This tree is also a noxious weed
Reading Time: < 1 minute Common buckthorn, otherwise known as European buckthorn, has been found in two locations in Alberta — in Edmonton along the North Saskatchewan River and in Stettler County. It was originally brought to North America from Eurasia as an ornamental, but soon spread throughout the continent. High seed production and excellent tolerance to Canada’s climate allow […] Read more

Noxious weed found throughout Alberta
Noxious Weeds: Wooly Burdock
Reading Time: < 1 minute Woolly burdock is found throughout Alberta and will grow in most soil types. It prefers moist, loamy, and well-drained soils which are in direct sunlight. This noxious weed is commonly found on disturbed sites, but has also been found growing in gardens for herbal use. Woolly burdock can only reproduce by seed, but is self-fertile […] Read more