Undesirable weeds
Ragweed and poison ivy are two undesirable weeds that are banned in Quebec for health reasons. In Dollard-des-Ormeaux, they are listed as a nuisance in By-law R-2014-094, which prohibits their presence on vacant or built-up land.
Undesirable plants establish themselves because the conditions of your land are favorable to them.
An environmentally-friendly solution to prevent or control the problem and to enhance the beauty your lawn is to use competitive perennials that are favorable to the condition of your soil. (e.g. clover, thyme, yarrow).
How to safely get rid of undesirable weeds
The use of pesticides is prohibited on the territory of Dollard-des-Ormeaux by By-law R-2015-099, as they are harfmul to human health, destroy surrounding vegetation and cannot be used in a localized way. Instead, try these ecological and sustainable ways to get rid of undesirable weeds:
Ragweed (ambrosia artemisiifolia)
Poison ivy (rhus radicans)
- Pull out manually with gardening tools before it flowers in early August, and before it goes to seed;
- Burn or scald it at the curb;
- Apply a low-impact herbicide locally when the grass is young;
- Cover with a tarp or mulch when the plant is young before flowering.
- Dispose in the garbage bin.
- Pull out manually, including its stems and underground roots, with suitable protection (gloves, long sleeves, no exposed skin.)
- Smother the plant for at least a year with geotextile fabric or another durable material.
- Spray with herbicide soap or acetic acid when the plant is young and small to prevent it from photosynthesizing throughout its growth period.
- Dispose in the garbage bin.
WARNING: do not burn poison ivy, as the fumes contain a toxic resin that can cause a severe allergic reaction.
How to identify these undesirable weeds
Ragweed (ambrosia artemisiifolia)
- Height: 6 to 90 cm (2 to 35 in)
- Leaves: laced and divided. Their color are a light green.
- Location: cultivated or vacant lots, bare lawns, curbs and roadsides. It grows easily where nothing else will.
- Allergies: Hay fever. The male flowers release allergenic pollen in August and September.
Poison ivy (rhus radicans)
Poison ivy has several forms: creeping, bushy and climbing.
- Height: 10 to 80 cm (4 to 31 in), and up to 10 m (32 ft) in the climbing form
- Leaves: three small oval leaflets with irregular outlines or no teeth. Reddish in spring, green in summer, and yellow, orange or red in autumn.
- Locations: Dry or damp, shady or sunny environments. Mainly found at the edge of woods; along fencerows, roadsides, cliffs, riverbanks and railroads.
- Allergies: When burning, the fumes contain a toxic resin that can cause a severe allergic reaction.
In case of contact - Care in case of exposure to poison ivy
If you come into contact with poison ivy, wash immediately with cold water without soap, then apply cold water compresses for 30 minutes, 3 to 4 times a day. If you feel itchy, simply apply baking soda mixed with water or calamine. If you need more information, don’t hesitate to call info-Santé 811, and in more serious cases, consult a doctor.
Resources
Reference
- Smeesters, Édith, Daniel, Anthony et Djotni, Amina, Solutions écologiques en horticulture pour le contrôle des ravageurs, des mauvaises herbes et des maladies, 2005. (free traduction)
- Ville de Dollard-des-Ormeaux, Règlement concernant les nuisances (R-2014-094), 2014.
- Meloche, Marc, Le guide québécois des mauvaises herbes, insectes nuisibles et maladies, 1988.
- Gift, Nacy, Good weed Bad weed who’s who, what to do, and why some deserve a second chance, 2011.
- Gouvernement du Québec, Reconnaître et éliminer l’herbe à la puce, 2023.