Managing Common Lawn Weeds: Ground Ivy, Moss, Mushrooms, and Bermuda Grass

Understanding and Controlling Ground Ivy

Ground ivy (Glechoma hederacea) is a persistent perennial weed that spreads via creeping stems rooting at the nodes. Its foliage releases a minty odor when mowed. This weed primarily invades turfgrass and landscapes, and it's notoriously difficult to control because it cannot be easily pulled from lawns. Many common broadleaf herbicides containing 2,4-D or MCPP (mecoprop) have little effect on ground ivy. However, dicamba (also known as Banvel) provides effective control. Most dicamba-based lawn weed killers also contain 2,4-D and MCPP, but repeat applications are often necessary for complete eradication.

Dealing with Moss in Lawns

Moss indicates poor turf health rather than being a direct cause of grass death. It thrives in conditions such as low fertility, soil compaction, poor drainage, excessive shade, and inadequate aeration. Moss does not kill grass; instead, it creates unfavorable growing conditions that eventually cause grass to die out. To eliminate moss, focus on improving grass-growing conditions: address drainage, reduce compaction, increase sunlight, and fertilize appropriately. Herbicides offer only short-term moss control and, without correcting underlying issues, moss will return. Lime applications raise soil pH but do little to prevent moss, as moss grows even on limestone and concrete.

Managing Mushrooms and Fairy Rings

Mushrooms are the fruiting bodies of soil fungi that appear during wet weather in spring and summer. They feed on buried organic matter like roots, stumps, or boards. Most mushrooms don't harm the lawn but are unsightly. Fairy rings—arcs or circles of dark green grass—expand 3 inches to 2 feet per season as the fungus grows outward. The fungus can interfere with water movement, stressing the turf. There is no chemical control for mushrooms; they disappear once the buried wood fully decays. For temporary control, break mushrooms with a rake or mower to dry them out and reduce ingestion risk by children. For individual mushrooms, remove the organic matter (dig up wood), then fill and reseed or sod.

Controlling Bermuda Grass Invasion

Bermuda grass is a fine-textured, warm-season annual that spreads rapidly during summer, often overtaking cool-season grasses while they are dormant. Hand-pulling before it gets out of control is more effective than herbicides. Apply a pre-emergent herbicide in spring to prevent seed germination. As a last resort, non-selective herbicides like fluazifop-butyl or glyphosate can kill all vegetation, followed by reseeding—but only if you plan to renovate the lawn entirely.