Tour opens eyes to weed war

It was a definite sign, when fieldman Oscar Anderson from Alberta’s Municipal District of Ranchland got off the bus at the Canada–U.S. border and began pulling weeds.

And that was even before he presented his passport to U.S. customs officials.

Anderson muttered something derogatory about scentless chamomile, one of many invasive weeds that plague Alberta and Montana, and other places.

Yes, it was a sign that travelling with a bunch of weed experts would provide a different perspective on the beautiful vistas available in both Wild Rose Country and Big Sky Country.

Two buses full of weed folks, water folks and agriculture folks — some of them wearing all three hats — drove out on the Transboundary Water, Weeds and Stewardship Tour Aug. 8-10.

Once across the 49th parallel, the buses rolled past waves and drifts and fields of purplish-pink plants in full bloom.

Pretty, you think?

Not so, groaned the weed experts. The tour had arrived at the opportune time to see spotted knapweed in full bloom. And knapweed is one of the nasties on the list of invasive plants in the Crown of the Continent, affecting parts of British Columbia, Alberta and Montana.

Why were these weed folks so glum? A single spotted knapweed plant can produce up to 40,000 seeds. Those seeds are easily spread and can remain viable in the soil for eight or more years. The plant has a deep taproot that resists pulling, it loves to grow in disturbed areas and it exudes a chemical in the soil that inhibits growth of the neighbouring plants.

Chemical controls are few and not easily applied in the mountains, ditches, gullies and gulches where the weed thrives. Biological controls are an option but they lack the instant gratification that would be welcome.

One begins to see why a field of purplish-pink plants perturbs people.

Tour participants heard about efforts to control knapweed and other invasives. The views from the bus windows showed the task is a daunting one, albeit one that every expert interviewed said was possible to tackle and control, if not eradicate.

The late Wayne Dyer said the only difference between a flower and a weed is judgment. Weed experts might agree. Their verdict on knapweed is: guilty.

About the author


Stories from our other publications