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Scientific Name

Cynoglossum officinale L. (ITIS)

Common Name

Houndstongue, Hounds tongue, gypsy flower, rats and mice, dog bur

Native To
Date of U.S. Introduction

First discovered in 1893 (Kedzie-Webb and Sheley 2017)

Means of Introduction

Introduced accidentally through contaminated seed (Kedzie-Webb and Sheley 2017)


Infests pasture and rangeland, where it is toxic to livestock (Kedzie-Webb and Sheley 2017)

Image use policy

Houndstongue, flowers


Photo by Mary Ellen (Mel) Harte

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Distribution / Maps / Survey Status


Selected Resources

The section below contains highly relevant resources for this species, organized by source.

Council or Task Force
  • Fact Sheet: Hound's Tongue [PDF, 700 KB]

    • Jan 2014
    • Alberta Invasive Species Council (Canada).

    • See also: Fact Sheets for more information about individual invasive species, including those listed as "Prohibited Noxious" and "Noxious" under the Alberta Weed Control Act

Federal Government
State and Local Government