Burdock plant ontario

Hem / Trädgård & Växter / Burdock plant ontario

This list is available on the NANPS’s website and features growers who specialize in native plants and do not sell invasive species.Please click below to access the list on the NANPS’s website and for further details.

NANPS Commerical Native Plant Growers List

Love our Grow Me Instead resources and want to see more?

They easily entangle feathers, particularly on smaller birds like warblers or finches, preventing them from flying or feeding properly. Non-native to Ontario

Burdock did not evolve within Ontario’s natural environment. Its seeds are designed to hitchhike: the burrs cling to animals, people, and even equipment, spreading easily over long distances.

Burdock root is edible and has a long history in herbal medicine, but when it escapes into wild or unmanaged spaces, it quickly turns into an ecological nuisance.

Why Is Burdock Considered Invasive in Ontario?

A plant is considered invasive when it is non-native, spreads rapidly, and disrupts local ecosystems by outcompeting native species.

In addition, each common burdock plant can produce between 6,000 to 17,000 seeds, yielding a substantial seed bank. Be vigilant, spread awareness, and—most importantly—don’t let the burrs spread further.

Common Burdock

Composite or Aster (Asteraceae family):
Arctium minus Bernh.
EPPO code:
ARFMI
Other names:
Burdock, burs, clotbur, lesser burdock, wild burdock, wild rhubarb

Species information

Lifecycle:
Biennial
Propagation:
Reproduces by seed.
Emergence:
Seedlings emerge early in the spring.
Range and habitat:
Most commonly found around field boundaries but can creep into cultivated fields especially in cropping systems with reduced tillage.
Competitiveness:
Unknown, but impedes crop establishment and can smother out other vegetation.

Identification clues

Leaves

Cotyledons:
Oblong with conspicuous veins.
Young leaves:
In a basal rosette, round to oval shape with wavy margins and prominent veins.
Mature leaves:
Resembling rhubarb but with undersides having white woolly hairs.

Mature plant

Stem:
Erect, 60–180 cm tall, branched, thick, hollow and grooved lengthwise.
Flowers:
round and densely covered with purplish to white hooked bristles, either having one on a short stalk or in clusters at the end of branches; flowers from July to September; when mature are brown and easily break off with the burs clinging to clothing, and animal fur; angular seed is contained within the burs.

Similar species

Common burdock is a very distinct plant that is rarely confused with any other plants.

The result is a plant that may appear harmless but causes cascading ecological effects when allowed to spread.

Conclusion

Burdock is indeed an invasive plant in Ontario, and its presence poses risks to both wildlife and native ecosystems. Their recommendations typically include:

  • Cutting the plant before it seeds (usually in late summer)

  • Digging out the deep taproot entirely

  • Avoiding mechanical mowing, which can lead to root fragmentation and regrowth

● Volunteer Cleanup Efforts

Community groups and volunteers have taken matters into their own hands.

Burdock fits all three criteria.

1. There is, however, another burdock plant in Ontario called “great burdock.” It is difficult to tell the two species apart at the vegetative stages but at the flowering stages there are two points of differentiation. If you’ve ever wandered through an Ontario park or trail and returned home with sticky burrs clinging to your clothes or your dog’s fur, you’ve likely encountered burdock—a tall, leafy plant with rough seed heads that latch onto anything they touch.

Here’s a recent encounter we had with a backyard full of 8-foot tall burdock.

While burdock may seem like just another common weed, it poses a serious problem to Ontario’s natural ecosystems.

Support us today by becoming a member, or making a donation to help Ontarians take action on invasive plant issues.

Hi, Dave here from Foxy Gardens in Southwestern Ontario, Canada. In urban areas, off-leash dogs are a major contributor to its spread.

3.

burdock plant ontario

The basal leaves of burdock in its second year are large and can shade out native plants, reducing diversity and altering community composition. tomentosum). Firstly, great burdock flowers are typically larger and with a paler colour. While it may have culinary and medicinal uses, its aggressive spread, ability to dominate disturbed environments, and harmful impact on birds and pets make it a priority for removal and management.

Whether you’re a gardener, a hiker, or a concerned citizen, taking action against burdock helps protect Ontario’s biodiversity.

All three are weedy species that share similar histories and biology, with some differences in identification features. But is burdock officially considered invasive in Ontario?

Yes—burdock is classified as an invasive plant in Ontario, and multiple organizations, including the Ontario Invasive Plant Council (OIPC) and Birds Canada, recognize its ecological threat.

As a result, it lacks natural predators or diseases that would otherwise keep it in check. Burdock roots can extend up to 3 or 4 feet, so use a spade or garden fork.

  • Cut Before Seeding: If full removal isn’t possible, cut the plant down before burrs form.

  • Do Not Compost Burrs: Dispose of them in yard waste or trash, not compost, to prevent reseeding.

  • Check Clothing and Pets: If you’ve walked through an area with burdock, inspect yourself and your pets for hitchhiking burrs.

    • Burdock: Useful, But Not Here

    It’s worth acknowledging that burdock isn’t all bad—in the right context.