Creeping buttercup (Ranunculus repens) is an aggressive perennial herbaceous weed, particularly troublesome in lawns, gardens, and pastures. This plant is a member of the buttercup family (Ranunculaceae) and its reputation as a nuisance stems from its relentless, low-growing nature and its dual method of propagation. Its ability to thrive in conditions often unfavorable to turf grass makes it a significant competitor. As a non-native species introduced from Europe, it has successfully naturalized across temperate regions.
Identifying Creeping Buttercup
Identification of Ranunculus repens relies on recognizing several distinct physical characteristics. The most noticeable features are the bright, glossy yellow flowers, which typically have five petals and appear from late spring through summer. These flowers are borne on slightly upright stems that rise above the foliage. The leaves are dark green and characteristically divided into three deeply lobed leaflets, often displaying pale or whitish blotches. This three-parted leaf structure helps distinguish it from other common weeds. Creeping buttercup maintains a low, spreading growth habit, forming a dense rosette of leaves, and is most frequently encountered in moist, poorly drained, and compacted soils, conditions that inhibit the growth of healthier, competing turf.
How Creeping Buttercup Spreads
The primary reason for the plant’s aggressive and invasive nature is its highly effective, dual-pronged reproductive strategy. Creeping buttercup is a stoloniferous plant, meaning it produces horizontal stems called runners that creep along the soil surface. These runners root down at the nodes wherever they make contact with the ground, establishing new, genetically identical daughter plants. A single parent plant can quickly colonize a large area, with its stolons spreading up to several feet in a single season. Beyond the runners, the plant also produces viable seeds in dense, bur-like clusters, which are dispersed and can remain dormant in the soil for many years, creating a persistent seed bank. This combination of rapid vegetative spread and long-term seed viability makes eradication a multi-year effort.
Strategies for Control and Eradication
Mechanical/Manual Control
For small, isolated patches, manual removal is a viable option, but it requires careful effort. The entire root system and all runners must be carefully dug up without breaking them, as any fragments left behind can quickly resprout. It is often easiest to perform this task when the soil is soft and moist, such as in the fall or spring, which allows the shallow root systems to be extracted more cleanly. Once removed, the plant material should be disposed of in a green waste bin or taken to a composting facility, never composted on site, to prevent regrowth from the runners.
Cultural Control
Addressing the environmental conditions that favor creeping buttercup is a foundational step in long-term control. This weed thrives in wet, compacted, and often acidic soils, so improving drainage is paramount. Incorporating organic matter, aerating the soil to reduce compaction, and applying lime to raise the pH level can create an environment more conducive to healthy turf growth. Increasing the density of desirable plants, such as by overseeding the lawn, helps the grass outcompete the buttercup for light, water, and nutrients.
Chemical Control
Chemical control involves using selective broadleaf herbicides that target the buttercup without harming the surrounding grass. Products containing active ingredients such as 2,4-D, triclopyr, or dicamba are commonly recommended for effective control. These systemic herbicides are most effective when applied to actively growing plants, typically from spring through fall, requiring repeat applications for complete eradication. For spot treatments on severely infested areas, a non-selective herbicide like glyphosate can be used, but extreme care must be taken to avoid contact with desired plants. Always follow the label directions precisely regarding application rates, timing, and safety precautions.
Toxicity Risks to Pets and Livestock
Creeping buttercup contains a naturally occurring compound called ranunculin, which is the source of its toxicity. When the plant is chewed, crushed, or damaged, ranunculin is converted into a highly irritating and toxic substance known as protoanemonin. Protoanemonin has a bitter taste, which fortunately acts as a deterrent, causing most grazing animals to avoid the plant. If ingested in large amounts, especially in overgrazed pastures, the toxin can cause serious health issues. Symptoms of poisoning in livestock and pets include excessive salivation, blistering around the mouth and face, colic, diarrhea, and vomiting. The toxic compound breaks down when the plant is dried, making buttercup-infested hay generally safe for consumption.