GFM Network News


The stem-mining weevil larvae live up to their name, burrowing down the length of Canada thistles and feeding on their leaves after becoming adults.

There’s a reason why stem-mining weevils are the priciest livestock in Alberta

The insects are mowing down Canada thistle across the province, and attracting lots of eager buyers

Tens of thousands of weevils have been pouring into Alberta from Montana — and producers are clamouring for more. “It’s a biological control and it’s been going great,” said Rachael Nay, conservation agriculture extension co-ordinator with the West-Central Forage Association. The association began the project to import stem-mining weevils four years ago as a way […] Read more

Perennial sow-thistle.

Perennial sow thistle costs farmers across Alberta

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

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


Devil’s trumpet — also known as jimsonweed, hell’s bells, loco-weed, and devil’s cucumber — is easily identified by either sight or smell.

Devil’s trumpet is a potentially deadly invader

Noxious Weeds: Jimsonweed

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

Yellow clematis gets its name from its lemon-yellow nodding flowers.

Another invader from the buttercup family

Cultivation is not successful and no chemicals are registered for control

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





Seed from Canada thistle can germinate eight to 10 days after flowering, but roots — not seeds — are the main way that this noxious weed spreads.

This quick-spreading weed gets an early start

Noxious weeds: Canada thistle

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

The size of this baby’s breath plant shows how well it can prosper in the Alberta landscape.

A wolf in sheep’s clothing

Noxious Weeds: Baby's breath

Many people think of baby’s breath as a cute, delicate filler flower found in rose bouquets. The real plant found in the Prairies couldn’t be further from this image. This weed has a taproot that can reach the astonishing depth of four metres, and it can grow as wide as 41 centimetres in circumference. And […] Read more



Weevil larvae offer up major damage to Canada thistle.

Canada thistle: Meet your worst nightmare

Every rancher hates this hard-to-control weed, but stem mining weevils just eat them up (from the inside)

Every year, Canada thistle takes a big bite out of the productivity of Alberta forage and grasslands. But an increasing number of producers is biting back — in a wholly natural way. In late August, the West-Central Forage Association will once again import hundreds of cartons of little black bugs from an insectary in Montana. […] Read more