GFM Network News


Stem-mining weevils have been successful at stopping the spread of Canada thistle, but the weevils are in short supply.

Supply can’t meet demand for thistle-munching weevils

Stem-mining weevils love Canada thistle but getting enough of the bugs has been a challenge for forage association

Canada thistle is a huge problem in ranchers’ fields — but unfortunately, demand for one of the solutions has outstripped supply. West Central Forage Association has been selling stem-mining weevils since about 2014 but recently its supplier in Montana has had production problems and been unable to fill its orders. “The last couple of years, […] Read more

Distinct markings give adult gall flies a rather striking appearance, while their larvae are anything but attractive. But they can do serious damage to a Canada thistle.

Tiny warriors get nasty on Canada thistle

Stem gall flies love to feed on — and breed in — the much-loathed and fast-spreading invasive weed

The West Central Forage Association has another biocontrol that can help you win the war against Canada thistle. The proud warriors are called stem gall flies and they’re available for sale. “The gall flies act on a different portion of the Canada thistle than the weevils do,” said Rachael Nay, conservation agriculture and extension program […] 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

Cereal stems move unscathed through the CombCut’s comb-like knives, while broadleaf weed stems are cropped close to the ground.

New Swedish machine slices problem weeds down to size

Organic grain growers have been snapping up CombCut machines ‘like crazy’

A new piece of machinery is helping crop growers control broadleaf weeds on their farms — especially on organic operations. “Organic growers are buying these CombCut machines like crazy,” said Steve Shirtliffe, a professor of plant sciences at the University of Saskatchewan. “There’s a real buzz in the organic farming community. I’ve never seen equipment […] Read more