Sticker weeds are common landscape invaders that transform comfortable lawns into painful hazards, inflicting physical discomfort. These aggressive plants are persistent, making their eradication a frustrating, multi-step process for homeowners seeking to reclaim their outdoor spaces. Successfully eliminating these pests requires accurately identifying the specific species present and timing control measures to interrupt their unique life cycles.
Identifying the Specific Sticker Weed Problem
Effective treatment for sticker weeds begins with distinguishing between the two most common culprits, which have opposing growth patterns. Lawn Burweed (Soliva sessilis), sometimes called spurweed, is a broadleaf winter annual. It germinates in the fall and remains low-growing throughout the cool winter months.
This weed develops spine-tipped burs in the leaf axils during early spring as temperatures warm. Once the burs harden into sharp stickers, chemical control becomes much less effective. The plant eventually dies off in the heat of summer, leaving the painful seeds behind.
Southern Sandbur (Cenchrus echinatus), by contrast, is a grass-like summer annual. Sandbur seeds begin to germinate in the late spring, often when soil temperatures reach 55 degrees Fahrenheit, and continue to emerge throughout the summer. This weed produces its spiny burrs in late summer and fall, with each bur containing several seeds. The control strategy for each must be highly specific.
Immediate Chemical Solutions for Existing Weeds
The immediate goal for managing existing sticker weeds, known as post-emergent control, is to eliminate the plants before they produce seeds. For Lawn Burweed, the application window is typically late fall through late winter, generally November through March, while the plant is actively growing but has not yet formed stickers.
Herbicides containing 2,4-D, dicamba, or mecoprop (often sold as “three-way” broadleaf weed killers) are effective against Burweed. Products with a higher concentration of dicamba tend to provide better control. Always check the product label to ensure the chemical is safe for your specific turfgrass type, as some warm-season grasses may require a reduced application rate to prevent damage.
Controlling the grass-like Southern Sandbur that is already visible is challenging because it grows within the lawn. Selective post-emergent herbicides like quinclorac can be used, but treatment is most successful when the Sandbur is still in its young, seedling stage. If the plants are older, a follow-up application may be necessary to minimize harm to the surrounding lawn.
Non-Chemical and Manual Removal Strategies
For small infestations or for homeowners avoiding herbicides, manual removal is an option, but timing is crucial. Weeds must be removed entirely, including the root system, before the burs mature and drop seeds into the soil. Hand-pulling Lawn Burweed in late fall or winter is effective while the plant is small, but requires wearing gloves to protect against forming spines.
For localized patches, targeted heat application using boiling water causes thermal shock to the plant cells. Pouring boiling water directly onto the weed will kill the foliage instantly, but this method is non-selective and will also kill desirable turfgrass nearby. This technique is best reserved for weeds growing in sidewalk cracks, driveways, or small, isolated areas.
Solarization offers a broader, non-chemical method to eliminate large patches of weeds and their seed bank simultaneously. This process involves watering the infested area and covering it with a clear plastic sheet for four to six weeks during the hottest summer months. The plastic traps solar heat, raising the soil temperature to levels that exceed 140 degrees Fahrenheit, which is lethal to many weed seeds in the top 6 to 12 inches of soil.
Long-Term Prevention and Lawn Health Management
The most effective long-term solution involves applying pre-emergent herbicides, which create a chemical barrier in the soil that prevents seeds from germinating. The precise timing of this application is paramount, requiring knowledge of the weed’s life cycle. For the winter annual Lawn Burweed, pre-emergent products containing active ingredients like prodiamine, isoxaben, or dithiopyr should be applied in the fall, typically late September to October, well before the seeds sprout.
Preventing the summer annual Southern Sandbur requires applying a pre-emergent product like pendimethalin or prodiamine in the early spring. This application should occur when soil temperatures consistently reach 52 to 55 degrees Fahrenheit, before the sandbur seeds begin to germinate. Using a split application six to eight weeks later can extend the control period against Sandbur’s prolonged germination window.
Promoting a dense, healthy turfgrass canopy is a simple yet powerful cultural practice that naturally discourages sticker weeds. Maintaining the proper mowing height helps the lawn shade the soil, reducing the light needed for weed seeds to germinate. Deep and infrequent watering encourages strong root growth in the turf, allowing the healthy grass to outcompete the weeds for available resources.