Glechoma hederacea L—Ground-ivy; gill-over-the-ground; creeping charlie; runaway-robin
FAMILY: Labiatae (Lamiaceae)—the Mint Family
This is a large group of plants known for glands that secrete pungent, volatile oils that may be toxic in large amounts. Many plants in this family are cultivated as ornamentals or as sweet herbs. Characteristic features for this family include stems: square in cross section; leaves: opposite, 4-ranked, simple, without stipules, glandular; flowers: irregular; calyx: 4- to 5-lobed, 2-lipped, persistent; corolla: 4- to 6-lobed, 2-lipped, petals conspicuously united; stamens: 4 (rarely 2), inserted on the corolla; ovary: superior, deeply lobed; style: 1 from the center of the ovary lobes; fruit: 4 one-seeded nutlets.
PHENOLOGY: Ground-ivy flowers April through June.
DISTRIBUTION: Found in moist fields or woods or in disturbed soil, including roadsides and yards.
PLANT CHARACTERISTICS: Plants are prostrate or creeping; leaves: cauline, petiolate, 1-3 cm, crenate rotund-cordate to cordate-reniform; stem: retrorsely scabrous to subglabrous; pilose at the nodes; flowers: 13-23 mm across, on short pedicels; petals: blue violet, marked with purple spots; usually 3 flowers per axil.
POISONOUS PARTS: All parts are toxic in green or dried condition.
SYMPTOMS: Salivation, sweating, dyspnea, panting, dilated pupils, anxious look, cyanosis, and possibly pulmonary edema can be manifested. Postmortem: pulmonary edema and cerebral hyperaemia.
POISONOUS PRINCIPLES: Physiologically active volatile oils are responsible for toxicosis.
CONFUSED TAXA: Glecoma is sometimes mistaken for Lamium (dead nettle), but the flowers are distinctly pediceled (in loose cymules) in Glecoma and sessile (in dense cymules) in Lamium.
SPECIES OF ANIMALS AFFECTED: Apparently only horses are susceptible to Glecoma toxins.
TREATMENT: (11a)(b); (26)
OF INTEREST: Lamjum amplexicaule L., commonly encountered as an element of our spring flora, causes "staggers" in sheep, horses, and cattle. Stachys arvensis L., fieldnettle, is responsible for nervous disorders in livestock, especially sheep. It too is a Pennsylvania resident.