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Caption: Comfrey bell-shaped flowers
Photo by: T.W. Miller
Weeds : Comfrey :
Symphytum officinale
(revision date: 6/9/2014)
Family: Boraginaceae
Cycle: Perennial
Plant Type: Broadleaf
Use Integrated Pest Management (IPM) for successful weed management.
Biology
Comfrey has clump-forming perennial roots with brown to black bark. The roots are thick and penetrate deep in the soil, making comfrey difficult to eradicate once established. Plants are from one to three feet tall. Leaves are thick and broad, growing primarily from the base of the plant, and are roughly hairy on both upper and lower surfaces. Lower leaves may exceed eight inches in length. Flowering stems rise from the center portion of the plant and bear somewhat inconspicuous dull bluish-pink (sometimes white, cream-colored, or purplish), bell-shaped nodding flowers. Fruits consist of four glossy, brownish-black nutlets or seeds joined at the base. SPECIAL INFORMATION: Although comfrey has a long history of both food and medicinal use, it should not be taken internally. The plant contains a toxic substance which can cause chronic liver damage. Comfrey may be confused with purple foxglove (Digitalis purpurea), which is toxic.
Habitat
Comfrey is most often found spreading from sites where it was introduced as an ornamental or herb. It prefers moist, rich soils and can be found in meadows and waste places.
Management Options
Non-Chemical Management
None recommended
Select non-chemical management options as your first choice!
Chemical Management
IMPORTANT:
Visit Home and Garden Fact Sheets for more information on using pesticides
Apply according to label directions. Not a problem in established turf areas. Glyphosate products should be applied as spot treatments only! NOTE: Some ingredients listed here are only available in combination. Read the label carefully on combination products to make sure the product is suitable for your specific situation.
Landscape areas
glyphosate
Turf areas
Bare ground areas
glyphosate
Images
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Caption: Comfrey bell-shaped flowers
Photo by: T.W. Miller
Caption: Comfrey leaf
Photo by: T.W. Miller
Caption: Comfrey bell-shaped flowers
Photo by: T.W. Miller
Caption: Comfrey in waste area
Photo by: T.W. Miller
Caption: Comfrey hairy stem
Photo by: T.W. Miller