Cynoglossum officinale is a biennial or short-lived perennial forb 30-120 cm tall. It reproduces by seeds. The stems are erect, robust, and green in colour.
It is easily identified by its rough-textured hound tongue-like leaves and its slightly droopy reddish-purplish to white flowers located in densely clustered panicles.
Houndstongue Classification
- Domain: Eukaryota
- Kingdom: Plantae
- Phylum: Tracheophyta
- Subphylum: Angiospermae
- Class: Dicotyledonae
- Order: Boraginales
- Family: Boraginaceae
- Genus: Cynoglossum
- Species: Cynoglossum officinale
- Common Names: Common Houndstongue, Houndstooth, Glovewort, Common bur, Dog burr, Woolmat, Beggar’s lice, Gypsy flower, Dog’s tongue, and Sheelice.
Nativity and Distribution
Houndstongue is native to Eastern Europe and Western Asia. Today, it is also found in Northern Europe and North America.
Physical Characteristics

- Leaves: Simple basal leaves with entire margins and petiolate stem leaves
- Fruits: Dark brown indehiscent burred fruits with four nutlets
- Stems: Can produce a single or multiple erect hairy stems (30-120 cm tall)
- Flowers: Reddish-purple (occasionally white) flowers arranged in racemes
- Roots: Tap root system
Cynoglossum officinale is a biennial or a short-lived forb with an erect habit to 1.2m in height. It is easily recognized by its oblong, pubescent, and rough-textured leaves and its slightly droopy reddish-purple flowers located in densely clustered panicles.
The stems are erect, hairy, coarse, and green in color. The lower leaves are alternate, lanceolate to oblong, hairy, 2-5 cm wide, and 10-30 cm long. They are arranged in rosettes and shaped like a hound’s tongue, hence the name.
The upper leaves are smaller (5-15 cm long), alternate, hairy, clasping to the stem, with entire margins.
Flowers are reddish-purple and occasionally white and about 6-9mm wide and 4-5mm long. They are arranged in racemes that grow on the axils of the branches and stem tips.
Each flower comprises five triangular-shaped sepals and 5 petals forming a funnel-like corolla. Flowering occurs between June and July.
The seeds are dark brown to black, 2-3mm long, triangular with a rounded bottom, and have a rough and wrinkled appearance.
Reproduction, Dispersal, and Life Cycle

- Life Cycle: Biennial or short-lived perennial
- Seeds: A single plant can produce 300-4,000 seeds per year
- Climate: Temperate zones
- Dispersal: Animals and contaminated produce
Cynoglossum officinale behaves as a biennial or a short-lived perennial and reproduces by seed.
In the spring of the first year, the young seedlings form a basal rosette and a strong root system (up to a depth of 3 feet) for storing reserves for the next growth stage. The next spring to summer, the plant bolts an erect stem (30-120 cm tall), flowers, and produces fruit.
The seeds attach to the fur of livestock and are dispersed to new areas. Secondary dispersal can also occur when the seed attaches to human clothing, equipment, and vehicles or as a contaminant of cereal produce.
One mature plant can produce 300-4,000 seeds which are generally highly viable. Higher seed germination is observed in seeds found 1-3 cm below the soil surface. Seeds buried further below are generally viable for 1-2 years.
Similar Plants
- Verbascum thapsus
- Hackelia virginiana
- Echium vulgare
- Lithospermum officinale
- Anchusa arvensis
Uses
Due to its calming and sedative effects, Cynoglossum officinale in its various forms has been used as a traditional medicine to treat various ailments and conditions.
The roots, leaves, and other parts of the plant have been used topically to treat piles, insect bites, and minor wounds.
Concoctions and teas have been used to treat diarrhea, dysentery, hepatitis, and trauma bleeding in China for many centuries.
The leaves are also used as a rodent repellent for stored vegetables.
Impact on Farms and Environment

Houndstongue is considered a noxious and invasive weed in many states in the U.S. and Western Canada. While it is a weed of sandy and disturbed areas, it is particularly a nuisance in pastures and rangelands. It competes for important resources, reducing desirable forage quality and quantity available for livestock.
C. officinale is not a desirable plant for animals and the basal leaves (which have the highest level of toxic alkaloids) can be poisonous to cattle, goats, and horses. While animals generally avoid the weed, it’s possible they can ingest it in contaminated hay.
The weed also attaches itself to animal fur, reducing their value and increasing veterinary care costs. Upon contact, it has also been reported to cause dermatitis in humans.
Control
- Mechanical control: Hand-pulling, cutting, and mowing
- Chemical control: Applications of herbicides containing Dicamba, 2,4-D amine, Imazapic, and Chlorsulfuron.
Hand pulling before seeding, cutting young rosette leaves or mowing flowering stems can be effective for small infestations. Tillage is a more viable control method for cropland infestations.
Chemical control offers better control for larger infestations. Consider applying herbicides containing dicamba, and 2,4-D amine to kill first-year rosettes.
Herbicides like metsulfuron, imazapic, and chlorsulfuron can eradicate the weed at any growth stage. Use of a surfactant with all applications is necessary to penetrate the hairy leaf surface.
When using any herbicide, read the label and follow all the instructions for the best results. If you’re unsure, consult a local expert.
Since there is no natural enemy to keep the weed in check, numerous potential biological agents have been released in search of effective control.
The most promising biological agent is the Mogulones boraginis. The weevil can single out the plant using visual, olfactory, and other cues and feed on up to 88% of its seeds. Take a look at the latest CABI project discussion for more information.

Lead Editor for Insight Weeds.