Burweed (also called spurweed or stickerweed) is a low-growing, winter annual plant notorious for producing sharp, spine-tipped burs. This invasive weed thrives in thin, stressed turfgrass, quickly establishing a foothold during cooler months. Eliminating this persistent nuisance requires a focused, multi-step natural approach. This strategy targets the plant’s life cycle while improving overall lawn health, avoiding reliance on synthetic chemicals.
Understanding Burweed’s Life Cycle
Burweed (Soliva sessilis) is a winter annual whose seeds germinate in the cool temperatures of the fall, typically around October. The newly sprouted plants remain small and inconspicuous throughout the winter, often blending in with dormant turf while expanding their root system. Rapid growth begins in early spring as temperatures rise. During this phase, the plant produces flowers and develops small, hooked burs in its leaf axils. Once these burs form and harden, they contain the seeds for the next generation. The most opportune time for natural control is during the small, vegetative stage in late winter or early spring, before the spine-tipped burs become visible.
Cultural Practices for Suppression
The primary defense against burweed is maintaining a dense, healthy turf that naturally outcompetes the weed for sunlight, water, and nutrients. Adjusting the mowing height is a simple and powerful cultural control. Setting the mower blade to three inches or more encourages the turfgrass to grow tall and thick, creating a dense canopy that shades the soil. This shade prevents burweed seeds from receiving the light necessary to germinate, disrupting the weed’s life cycle.
Soil compaction encourages burweed growth, as the weed tolerates poor soil conditions better than healthy turfgrass. Core aeration should be performed to alleviate compacted soil, creating small holes that allow water and air to penetrate the root zone. This process strengthens the turf’s root system, making the grass more resilient and less susceptible to invasion. Proper irrigation techniques are also essential for promoting deep, robust turf roots.
Watering the lawn deeply and infrequently is superior to light, daily sprinklings. Aim to apply about one inch of water per week in a single session, allowing the water to soak several inches into the soil. This practice encourages grass roots to grow deep to seek moisture. The shallow-rooted burweed struggles to survive the drier surface conditions between waterings, making the turf an inhospitable environment.
Hands-On Natural Removal Methods
For existing infestations, active, non-chemical removal methods provide immediate results. Manual removal is highly effective for isolated plants or small patches, provided it is done before the burs form in the spring. Using a weeding fork, carefully dig out the entire plant, ensuring the fibrous root system is completely extracted. Dispose of the weeds properly, as leaving them on the lawn allows immature burs to dry and drop their seeds.
For larger, heavily infested areas, smothering and solarization offer natural, large-scale control. Smothering involves covering the patch with a thick layer of organic mulch, such as wood chips or compost, which blocks sunlight and physically prevents growth. Alternatively, solarization involves covering the area with clear plastic sheeting secured tightly around the edges. The sun heats the trapped air and soil beneath the plastic, killing the burweed plants and their dormant seeds below the surface.
Targeted spot treatment with horticultural vinegar is effective, especially for younger plants. Unlike household vinegar, horticultural-grade solutions contain a higher concentration of acetic acid (15% to 30%). This potent acid acts as a contact herbicide, rapidly dehydrating the plant tissue upon application. For best results, mix the vinegar solution with a small amount of dish soap to help it stick to the waxy leaves. Always apply these solutions on a sunny, calm day, exercising caution to avoid damaging surrounding turf or irritating skin and eyes.