Weed of the Month: Creeping Charlie

Creeping Charlie is bitter and horses generally do not graze it unless it is the only forage available.

Photo: Kaldari/Wikimedia Commons

Common name: Creeping Charlie, ground ivy
Scientific name: Glechoma hederacea L.

Life Cycle: Creeping perennial
Origin: Eurasia
Poisonous: Yes

Ground ivy is distributed widely across the United States, except for in the desert Southwest. It grows in lawns, flowerbeds, and pastures. Horse pasture infestations are more severe during overgrazed or other conditions that inhibit grass growth.

Ground ivy is a member of the mint family that creeps along the ground and can grow to three feet or more in length. The stems are square, and flowers are a reddish-purple.

Toxicity: This plant is bitter and horses generally do not graze it unless it is the only forage available. All plant parts are toxic, including when it is in cured hay. Generally, horses must consume large quantities for a toxic reaction to occur. Excessive salivation, difficulty with breathing, excessive sweating, and dilated pupils are clinical signs that occur more frequently when this weed is a component of cured hay.

Ground ivy is not easily controlled. Hand-weeding is ineffective because all roots will not be removed and regrowth occurs. Mowing is ineffective because the weed grows horizontally. Herbicides are available for control in horse pastures. Consult your local Cooperative Extension Service personnel for herbicidal control options in your area.

William W. Witt, PhD, emeritus professor in the Department of Plant and Soil Sciences at the University of Kentucky, provided this information.

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