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Do you know the difference between restricted, noxious and nuisance weeds?

Learn all about weeds in our blog.  Information compliments of the Agricultural Industry AAA Fieldmen, Environment, Health & Safety handbook.

The Weed Control Act

Alberta’s Weed Control Act exists to enforce the control of weeds in order to protect landowners and our environment.  The act charges landowners with the responsibility to control weeds on their property, so as to prevent the spread to adjacent properties.  For the purposes of The Weed Control Act, weeds are designated into one of three categories:

I.  Restricted Weeds

Weeds in this category pose a serious threat, and as such must be eradicated.  Generally, these weeds possess characteristics of rapid spread, and superior competition.  These weeds are usually found in small numbers in Alberta, and are designated restricted to prevent their establishment.  Individual municipalities have the power to, and from time to time do elevate certain species to restricted status.  Check with your local municipality for weed designations in your area.

Handling Procedures:  Restricted weeds are to be eradicated.  Contact the local municipality, or agricultural Fieldman and inform them of the location before taking any action.  Many of these infestations require hand pulling, but in some circumstances other controls may be necessary.

Common restricted weeds in Alberta include:  Dodder, Eurasian Water Milfoil, Nodding Thistle, Yellow Star-Thistle, Diffuse Knapweed, Spotted Knapweed

II.  Noxious Weeds

Weeds designated noxious have the ability to spread rapidly, and cause severe crop losses and economic hardship.  These weeds must be controlled to prevent further establishment, and spread.

Handling Procedures:  When working on an easement/right of way where noxious weeds are present, all equipment must be thoroughly cleaned (ie steam cleaned) before proceeding to the next section of the job.  Noxious weeds shall not be transferred from one property to the next or from one county to the next.

Common noxious weeds in Alberta include:  Canada Thistle, Perennial Sow-Thistle, Scentless Chamomile, Ox-Eye Daisy, Common Tansy, Toadflax (Common/Yellow), Leafy Spurge, Purple Loosestrife

III.  Nuisance Weeds

These weeds are common to the Province, and in many cases are native species.  They can be found on nearly all land throughout the Province, and as such are very difficult to eradicate.  They can cause significant economic losses, but are so biologically suited that they cannot effectively be eradicated.

Handling Procedures:  Every attempt should be made to prevent the spread of weeds.  Equipment should be thoroughly cleaned between jobs.

Common nuisance weeds in Alberta include:  dandelions, chickweed, clover and burdock.

Control & Handling of Restricted, Noxious and Nuisance Weeds

An inspector who finds any restricted or noxious weeds in or on any land, premises, vehicle, standing crop, hay, fodder, machine, grain, elevator, crop processing plant, or equipment shall give notice to destroy the restricted weeds, and may give notice to control noxious weeds.

For nuisance weeds the inspector may issue a notice to prevent the spread of these weeds.

Green Oasis offers a variety of weed control services to help you get rid of those pesky weeds including 3 lawn care packages.  Contact your local office to learn more:

Calgary:                                                                Red Deer:

Tel:  403-206-9900                                             Tel:   403-358-3339


Learn more about Prohibited Noxious Species compliments of Alberta Invasive Species Council here.