Scouting for weeds: Ground ivy (creeping Charlie)
Editor’s note: This article is from the archives of the MSU Crop Advisory Team
Alerts. Check the label of any pesticide referenced to ensure your use is
Family. Lamiaceae (Mint) (view images)
Life cycle. Prostrate, creeping perennial.
Leaves. Opposite, kidney-shaped to rounded leaves are approximately 1 inch wide with scalloped margins, palmate veins and long leaf stalks. Damaged leaves emit a mintlike odor.
Stems. Prostrate, creeping stolons are square in cross-section and root at the nodes to form thick patches.
Flowers and fruit. Purplish blue, funnel-shaped flowers with two lips are found in clusters in the upper leaf axils. The upper lip has two lobes; the lower lip has three lobes. Fruit are small, brown, egg-shaped nutlets.
Reproduction. Creeping stems and seeds.
Control. Ground ivy is an aggressive, difficult-to-control weed in lawns. It often thrives in damp, shady areas of the lawn, but can tolerate full sunlight. Hand removal can be effective with small patches of ground ivy. The square stolons (aboveground stems) creep in the thatch layer of the turf. These stems can be carefully removed with success, but persistence and patience will be required.
Homeowners have several herbicide options that can be very effective for ground ivy control if applied at the correct time. Effective products include any of the “3-way” broadleaf herbicides for lawns, such as Weed-B-Gon Lawn Weed KillerÒ, TrimecÒ, Bayer Advanced Lawn Weed Killer for LawnsÒ, etc.. These 3-way products contain a mixture of dicamba, 2,4-D and MCPP/MCPA. For optimum control of ground ivy in the spring, two applications of a 3-way herbicide should be applied approximately 30 days apart beginning at flowering. A single application in the fall is usually the most consistent. Products that contain the active ingredient triclopyr, such as Weed-B-Gon Chickweed, Clover, and Oxalis Killer®, can sometimes be more effective than the three-way mixtures listed above. Remember, always read and follow labeled directions.
Controlling ground ivy with borax laundry detergent has been successful for some homeowners. Borax contains the element boron and all plants require relatively small amounts of this element. Ground ivy is more sensitive to high concentrations of boron than the cool-season lawn grasses. Therefore, ground ivy can be selectively controlled or suppressed in the lawn due to boron toxicity. Note: MSU has not regularly tested the use of borax in Michigan. There are problems with the use of borax just as with any other control method, such as soil type, environmental condition during or shortly after application, application timing and application rate. Contact the MSU Turf program for additional information at 517-355-0271.
Editor’s note: This article’s identification information is from the new field guide An IPM Pocket Guide for Weed Identification in Nurseries and Landscapes. For ordering information, call 517-353-6740 or visit: http://www.ipm.msu.edu/pdf/pocketGuidesLandsc07.pdf