Ground ivy is a creeping weed that appears in early spring through the first mowing of the year. Although mowing ground ivy will help to control it, it will not kill the plant. To prevent ground ivy from returning yearly, you must kill the plant with an herbicide.
Ground ivy is a relative of the mint family. The plant has large, round or kidney shaped leaves with scalloped margins. It spreads on creeping stems that root at the nodes where foliage sprouts from the ground. If you mow the plant, it releases a minty smell. Ground ivy is often confused with other creeping weeds, such as speedwell or common mallow. To confirm that you have ground ivy, you should examine the stem. Ground ivy has a square stem, while common mallow and speedwell both have rounded stems. Identifying your weed as ground ivy is important for selecting the right weed killer.
Ground ivy can be difficult to remove with cultural methods. Cutting, pulling or plowing up the plant will not eradicate it, thanks to ground ivy's rooting habit. Instead, plants must be killed with a broadleaf herbicide. Systemic herbicides containing glyphosate will not successfully kill ground ivy and will instead kill neighboring grass. A broadleaf herbicide will instead kill ground ivy and other broadleaf plants such as shrubs and trees, but will leave grassy plants such as turf grasses or grains alone.
According to North Dakota State University, a broadleaf weed killer such as Trimec is recommended for killing weeds such as ground ivy. Mix Trimec with a wetting agent such as water, according to the package directions, and place it in an applicator such as a pressure sprayer. Then apply the broadleaf herbicide to ground ivy once every 30 to 35 days. It will take repeated spraying of Trimec to completely remove ground ivy from your grass. Use approximately 1.5 oz. of Trimec per 6 gallons of water for every 1,000 square feet of grass that you want to treat.
Broadleaf herbicides act to inhibit a plant from producing energy through chlorophyll. The herbicide may change the pigment of the leaf to make the plant unable to absorb energy from the sunlight, or it may stop the chemical process of photosynthesis within the plant. Once a plant can no longer make food from sunlight, it slowly withers and dies.
The symptoms of the herbicide working within the plant appear in older leaves first. The older vegetation may produce yellow streaks along the veins. The leaves will gradually turn brown and die. Herbicides used in more alkaline soils may show a greater degree of effectiveness.