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Common burdock. Photo Credit: K. George Beck and James Sebastian, Colorado State University, Bugwood.org -
Common burdock first year leaves. Photo Credit: Ohio State Weed Lab, the Ohio State University, Bugwood.org -
Common burdock flowers and leaves. -
Common burdock burrs. Photo Credit: (c) Aaron I. Liston, courtesy of OregonFlora -
Common burdock.
Also known as: Small burdock, wild burdock, burdock, wild rhubarb.
Common burdock is a prickly plant. It is so prickly that its bractsBracts Leaf-like structures below a plant’s flower. are the inspiration for Velcro! A Swiss investor tired of pulling burdock burrs from his dog’s fur, so he examined them closely and came up with the idea for Velcro.
Description:
| Life Cycle: | Biennial (life cycle lasts two years) |
| Early Detection and Rapid Response species: | No |
| Height: | Up to 6 feet (2 meters) |
| Leaf Description: | In the first year of growth, common burdock forms a large, egg-shaped rosette. Its second-year leaves narrow to form a heart and grow alternately along its flowering stem. Both leaves are dark green, have wavy edges and woolly undersides. |
| Fruit & Flower Description: | Flowers bloom in clusters. Its flowers range in color from light lavender to deep violet and are surrounded by spiny bracts. Its bracts form stiff, brown hooks that attach to clothes and fur. As common burdock’s flowerheads mature, they dry and form a burr which contains its seeds. A single plant can produce 15,000 seeds. |
| Bloom Time: | July to September |
Habitat:
- Common burdock is often found in riparian areasRiparian Areas Areas of land that occur along the edges of rivers, streams, lakes, and other bodies of water., along roads, fences, and the edges of agricultural fields and pastures.
- It grows in full sun to full shade and prefers moist, well-drained soil.
Impact:
- Common burdock is known to harbor pathogensPathogens A bacteria, virus, or microorganism that causes disease., such as powdery mildew and root rot which can quickly spread and reduce crop yields.
- If burdock is present in sheep pastures, its burrs can become entangled in wool. This reduces the quality and value of the wool.
What you can do about it:
- Prevention is critical for controlling the spread of common burdock. If you are visiting an area with burdock, make sure to check your clothing, equipment, and pets’ fur for its barbed burrs.
- Mechanical controls such as hand pulling, deadheading, mowing, and tilling are effective for controlling large infestations and small patches.
- If you are deadheading its flowers, make sure to dispose of all flowerheads in a tied plastic bag in the trash. All other plant material can be composted.
Look-alikes:
Common cocklebur (Xanthium strumarium) and common burdock have similar shape and flowerheads. Common cocklebur leaves are kidney-shaped and have toothed edges while common burdock’s leaves are heart-shaped and have smooth edges.
Noxious Weed Listing:
| State of Oregon: | Not listed |
| State of Washington: | Not listed |
More Resources:
Download Common Burdock Best Management Practices Factsheet
- Pacific Northwest Weed Management Handbook: Common burdock