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Hounds tongue

(Cynoglossum officinale)

Photo of hound's tongue
Photo credit: Robert Videki, Doronicum KFT,

An herbaceous biennial that can grow 1-4' tall on a single stem that branches above.

Overview map of hound's tongue classification in WI
Restricted (orange) counties

Other names for this plant include:

  • Common names: ordinary hound's tongue, gypsy flower, dog's tongue
  • Scientific names: Cynoglossum officinale L.f. bicolor

Classification in Wisconsin: Restricted

Ecological Threat
  • Invades pastures, roadsides, grasslands, riparian areas and meadows.
  • Alkaloids in the plant decrease toxicity as it matures, yet they can still be toxic to horses and cattle.

Leaves: Elliptical, alternate leaves are dark green and slightly hairy. In the rosette stage, leaves are 6-8" long; in the second year, basal leaves are up to 12" long and reduce in size as they progress up the stem.

Flowers: Arranged in panicles in the upper leaf axils, red-purplish flowers bloom from June-July. They are up to 0.3" wide, have five petals and are saucer to funnel-shaped.

Fruits & seeds: Each flower produces four nutlets, or small nuts, covered in barbs. Nutlets that remain on the plant are viable for 2-3 years.

Roots: Large, woody taproot.


Mechanical: Mow second-year plants while in the flowering stage before seed production. Use a sharp shovel to cut 1-2" below the soil surface.

Chemical: Foliar spray rosettes in spring using 2% solutions of picloram, dicamba, or metsulfuron.

Sources for content:
  • The University of Washington - The Burke Museum of Natural History and Culture.
  • Cynoglossum officinale [exit DNR]. Klinkenberg, Brian. (Editor) 2009. E-Flora BC: Electronic Atlas of the Plants of British Columbia []. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Accessed: 8/21/2009 10:15:40 AM].
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