| | What are restricted, noxious and nuisance weeds?
Restricted, noxious and nuisance weeds are aggressive, difficult to manage, and invasive plant species. These weeds may displace or significantly alter native plant communities and may also cause economic damage to private and public lands. Legislation in Alberta, the Alberta Weed Control Act recognizes these three classes of weeds and is in place to keep these problem weeds from being introduced to Alberta or from spreading if they are already present. Each class of weeds is treated differently.
What is the difference between restricted, noxious, and nuisance weeds?
Restricted weeds are usually found in very few regions of Alberta and usually low populations are present at any one location. They are designated Restricted to prevent their establishment. Where found, “Destruction” of the restricted weeds is required. Noxious weeds are already established in many regions of the province. “Control” of noxious weeds is required where they are identified as problematic. “Destruction” and “Control” are defined in the Weed Control Act. Nuisance weeds are common species that can be found throughout the Province, and as such are very difficult to eliminate. They can cause significant economic losses, but are so biologically suited to Alberta that they cannot be eradicated.
Why are some noxious weeds listed in the Weed Control Act designated as a restricted weed in my municipality?
Municipalities have the legislative power to upgrade the status of a weed listed in the Weed Control Act as noxious to restricted as they deem necessary but cannot lower the status. This also holds true for nuisance weeds being upgraded to noxious or restricted status by the municipalities.
What weeds are classified as restricted, noxious, or nuisance in Alberta?
Restricted weeds in Alberta are:
Red bartsia - Odontites serotina L.
Diffuse knapweed - Centaurea diffusa L.
Spotted knapweed - Centaurea maculosa L
Nodding thistle - Carduus nutans L.
Eurasian Water Milfoil - Myriophyllum spicatum L.
Dodder - Cuscuta spp.
Yellow star thistle - Centaurea solstitialis L.
Noxious weeds in Alberta are:
Russian knapweed - Centaurea repens L.
Field bindweed - Convolvulus arvensis L.
White Cockle - Lychnis alba
Bladder campion - Silene cucubalus
Cleavers - Galium aparine L. and Galium spurium
Hoary cress - Cardaria spp.
Knawel - Scleranthus annuus L.
Perennial sow thistle - Sonchus arvensis L.
Cypress spurge - Euphorbia cyparissias L.
Leafy spurge - Euphorbia esula L.
Stork's bill - Erodium cicutarium L.
Canada thistle - Cirsium arvense L.
Toadflax - Linaria vulgaris
Persian darnel - Lolium persicum
Scentless Chamomile - Matricaria maritima L
Common tansy - Tanacetum vulgare L.
Blueweed - Echium vulgare L.
Spreading dogbane - Apocynum androsaemifolium L.
Field scabious - Knautia arvensis (L.) Duby
Hound's-tongue - Cynoglossum officinale L.
Oxeye daisy - Chrysanthemum leucanthemum L.
Tall buttercup - Ranunculus acris L.
Purple Loosestrife - Lythrum salicaria
Nuisance weeds in Alberta are:
Dalmatian toadflax - Linaria dalmatica L.
Wild radish - Raphanus raphanistrum L.
Creeping bellflower - Campanula rapunculoides L.
Hedge bindweed - Convolvulus sepium L.
Bluebur - Lappula echinata
Downy brome - Bromus tectorum
Tartary buckwheat - Fagopyrum tataricum
Wild buckwheat - Polygonum convolvulus
Biennial campion - Silene cserei
Night-flowering catchfly - Silene noctiflora L.
Common chickweed - Stellaria media L.
Field chickweed - Cerastium arvense L.
Mouse-eared chickweed - Cerastium vulgatum L.
Rough cinquefoil - Potentilla norvegica L.
Cow cockle - Saponaria vaccaria L.
Flixweed - Descurainia sophia L.
Green foxtail - Setaria viridis L.
Quack grass - Agropyron repens L.
Narrow-leaved hawk's-beard - Crepis tectorum L.
Hemp nettle - Galeopsis tetrahit L.
Henbit - Lamium amplexicaule L.
Lady's-thumb - Polygonum persicaria L.
Round-leaved mallow - Malva rotundifolia L.
Ball mustard - Neslia paniculata
Dog mustard - Erucastrum gallicum
Green tansy mustard - Descurainia pinnata
Wild mustard - Sinapis arvensis L.
Wormseed mustard - Erysimum cheiranthoides
Wild oats - Avena fatua L
Redroot pigweed - Amaranthus retroflexus L.
Shepherd's-purse - Capsella bursa-pastoris L.
Annual sow thistle - Sonchus oleraceus L.
Corn spurry - Spergula arvensis L.
Stinkweed - Thlaspi arvense L.
Russian thistle - Salsola pestifer
Dandelion - Taraxacum officinale
How do I manage restricted, noxious, and nuisance weeds?
To comply with the Weed Control Act, problem weeds can be managed by mechanical, chemical, and biological control measures but chemical and mechanical control are most common. Restricted weeds are difficult to deal with and often the only effective means of destruction is hand-picking. Agricultural or industrial herbicides are available to control most nuisance weeds and many noxious weeds. Biological control by insect or bacteria may be an option in some situations, but effective control agents have only been developed for a limited number of problem weeds. If restricted or noxious weeds are present on your land or in a public area, please contact your local Ag Fieldman to discuss control strategies.
Who is the Ag Fieldman in my area?
Please choose the following region to find out who is your local Ag Fieldman, contact your local municipality office, or contact the Agricultural Service Board Program at (780) 427-4213.
Central Region
Peace Region
Northeast Region
Northwest Region
South Region
Reference:
Weed glossary adapted from Weed Management – Telus, Alberta Ag Fieldmen Association, Ducks Unlimited – D. Bigelow, B.Vanden Born, S. Bayley contributors
1Red bartsia picture source: Wisconsin State Herbarium, Emmet J. Judziewicz photographer
2Red bartsia information from Manitoba Agriculture
Pictures courtesy MD of Willow Creek unless otherwise noted
Prepared by Colin Bergstrom, Alberta Ag-Info Centre, Alberta Agriculture and Rural Development |
|