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 Houndstongue flowers.

Houndstongue in burned area.


Houndstongue nutlets.


Interesting Facts

  • The plant’s name may have come from the shape and texture of the leaf resembling that of a dog’s tongue. Or that the name came from the belief that a leaf worn in the shoe could ward off dog attacks.
  • Extracts of the roots and leaves of houndstongue have been used in folk remedies for various ailments including fever, eczema, acne, and hemorrhoids.
  • An ointment derived from houndstongue is reported to cure baldness.
  • The red pigments of the outer root surface are anti-bacterial and may have wound healing abilities.
  • Roots and leaves have been used as pesticides and used to repel moles and other rodents for stored foods.
  • The foliage is toxic to domestic and wildlife.
  • Houndstongue is dispersed primarily through seeds adhering to livestock and wildlife.


A stout, erect perennial forb in the borage family.

Stems are upright, branched in the upper portion, and can grow to 30 inches tall.

Leaves are oblong with numerous soft white hairs on both surfaces. They have distinctive veins, smooth margins ,and can be up to 12 inches long.

Flowers are reddish-purple, have 5 petals and hang in clusters.

Seed/Fruit are flat, teardrops shaped, and have a hard spiny husk with barbs. Protruding barbs adhere to fur or fleece of wildlife, domestic animals, and human clothing.


Prefers drier, well-drained sites, but is tolerable to alkaline soils. Houndstongue is often associated with disturbed sites. It is also shade tolerant and can be commonly found under trees and shrubs where livestock and wildlife bed down.

Ecological Impacts

Houndstongue readily displaces native plant species and can establish monocultures. Nutlets that entangle in the wool or hair of livestock may create problems for ranchers that have to remove the burs. Another major concern is the threat of livestock poisoning. Although a live plant is unpalatable, livestock may ingest houndstoungue that may get into hay.


Mechanical: Mowing prior to flowering will prevent seed production. Hand pulling can be effective as long as the root is removed with the plant.

Chemical: Picloram, dicamba, and metsulfuron methyl are proven to be effective. Chemical treatment should be applied during the bolting or rosette stage since seed can be produced from a mature plant sprayed with a herbicide. Being a restricted-use herbicide, Picloram should only be applied by a state certified applicator. Contact your local county weed and pest office for more information.

Biological: There are no approved biological control agents approved for release in the United States.