Common burdock
Discuss this plant with the guide — choose this profile as a possible match and prepare your observations for Colorado Plants & Practical Care.
Arctium minus
Colorado noxious weed · List C — Manage widespread weeds. CO-rules-2025
Widespread and well established. Control is recommended by the state; local governments may require management. This is a management category, separate from danger ratings. Category source · What the lists mean.
Burs and fine bristles injure animals. Exposure help.
Still researching this plant
This is a sourced working profile. The cited findings are available below. Independent botanical and veterinary review is pending. Uncertainty is not a finding that the plant is safe.
Three views of this plant
Source-identified reference photographs; these are not a complete identification key. A source location outside Colorado does not establish local occurrence.
Isidre blanc · CC BY-SA 4.0
Photo source and identification
Original record · Original image
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Source page scientific identification plus visual morphology review of the selected photograph. This is a source-identified reference image, not a specimen-based taxonomic determination.
Wikimedia server-resized derivative; no crop, color change, or generative editing. Gallery display preserves the full image; the catalog preview uses a CSS crop.
Alberto Salguero Quiles · CC BY-SA 3.0
Photo source and identification
Original record · Original image
Source page scientific identification plus visual morphology review of the selected photograph. This is a source-identified reference image, not a specimen-based taxonomic determination.
Wikimedia server-resized derivative; no crop, color change, or generative editing. Gallery display preserves the full image; the catalog preview uses a CSS crop.
Alberto Salguero Quiles · CC BY-SA 3.0
Photo source and identification
Original record · Original image
Source page scientific identification plus visual morphology review of the selected photograph. This is a source-identified reference image, not a specimen-based taxonomic determination.
Wikimedia server-resized derivative; no crop, color change, or generative editing. Gallery display preserves the full image; the catalog preview uses a CSS crop.
Recognize
A large-leaved biennial with purple flowerheads that mature into hooked burs. Leaf undersides are woolly. N-arctium-minus
Plants & habitat
Burs hitchhike on animals and clothing; persistent seeds and deep taproots make established patches difficult to remove. N-arctium-minus
People
Burs and tiny bristles can irritate eyes, skin and airways. Avoid breaking apart dry burs near the face. N-arctium-minus
Dogs & cats
The source specifically reports eye, skin and respiratory injury in dogs. Cats can also contact burs, but cat-specific outcomes were not assessed. N-arctium-minus
Other animals
Bristles can injure horses and livestock; burs can entangle small wildlife. N-arctium-minus
Before taking action
Confirm identification and the requirements of your county weed program. For chemical treatment, follow the current product label, including restrictions around animals and water. S27
References
- CO-rules-2025 — Colorado Noxious Weed Act rules, 8 CCR 1206-2, Colorado Secretary of State / Department of Agriculture. Accessed 2026-09-07T01:07:48+00:00. Locator: Parts 3.1, 4.1, 5.1; management provisions; effective May 15, 2025.
- N-arctium-minus — arctium minus — Plant Toolbox, NC State Extension. Accessed 2026-09-07T01:04:55+00:00. Locator: Description; Attributes; Problems; Poisonous to Humans.
- S27 — 2103 – Colorado Noxious Weeds, PlantTalk Colorado · CSU Extension. Accessed 2026-09-07T00:23:57+00:00. Locator: List A, B and C management categories.