The presence of painful burrs or prickles in the lawn transforms a comfortable yard into a nuisance, often making it impossible to walk barefoot. These “stickers” are the hardened seed capsules of common weeds that have completed their life cycle and are now focused on spreading their seeds. Eliminating these weeds requires understanding their specific biology and applying precise control methods at the correct time of year. The most effective approach involves a combination of immediate eradication of existing plants and long-term prevention of future generations.
Identifying the Sticker Culprits
Effective treatment begins with correctly identifying the specific weed species responsible for the burrs, as their life cycles determine the window for successful control. The two most frequent culprits are Lawn Burweed and Puncturevine, also known as Spurweed and Goathead, respectively. Lawn Burweed (Soliva sessilis) is a low-growing, cool-season annual that germinates in the fall and grows inconspicuously through the winter. Its spine-tipped burrs form in the leaf axils during the early spring as temperatures warm, making them noticeable just before the plant naturally dies off.
Puncturevine (Tribulus terrestris) is a warm-season annual that thrives in hot, dry conditions and germinates in the spring or early summer. It forms dense, prostrate mats with yellow flowers, and its distinctive, tack-like seed burrs develop throughout the summer months. Unlike burweed, the puncturevine’s deep taproot allows it to compete aggressively for water, and its burrs can remain viable in the soil for several years, creating a persistent problem.
Targeted Chemical Eradication
Eliminating active sticker weeds requires post-emergent herbicides, which are applied directly to the foliage of the growing plant. For treating weeds within an established lawn, selective broadleaf herbicides are necessary, as they target the weed without harming the surrounding turfgrass. Products containing a mixture of active ingredients, such as 2,4-D, Dicamba, and MCPP (mecoprop), are recommended for effectiveness against a wide range of broadleaf weeds.
Application timing is critical; the herbicide must be applied when the weed is young and actively growing, ideally before the burrs begin to harden. For Lawn Burweed, this means treating during the cooler winter months, typically December through February. Once the spine-tipped burrs are fully formed in spring, killing the plant will not eliminate the existing seed capsules. Non-selective herbicides, like those containing glyphosate, should only be used for spot treatment in non-turf areas, such as cracks in sidewalks or driveways, as they will kill any vegetation they contact.
Non-Chemical Removal Techniques
For those preferring to avoid synthetic chemicals, several non-chemical methods can be employed to manage sticker weeds. Manual removal through hand-pulling or hoeing is effective for small infestations, but the entire root system must be removed to prevent regrowth. It is essential to bag and discard any weeds that have already formed burrs to prevent them from scattering seeds back into the soil.
A stronger lawn provides natural resistance, as a thick, healthy turf crowds out weeds by competing for light, water, and nutrients. Adjusting cultural practices, such as mowing at the correct height and ensuring proper fertilization, promotes a dense stand of grass that makes it difficult for weeds to establish. Organic spot treatments utilizing horticultural vinegar (20% to 30% acetic acid) can quickly dehydrate and kill young weeds. However, these high-concentration products are non-selective and will damage the surrounding turf, requiring careful, targeted application.
Stopping the Seeds Before They Start
The most effective long-term strategy for sticker control involves breaking the weed’s life cycle before the seeds can germinate using pre-emergent herbicides. These products create a chemical barrier near the soil surface that inhibits cell division in newly sprouting seeds, causing them to die before they emerge. Timing the application precisely is paramount, as the barrier must be in place before the seeds begin to sprout.
For warm-season annuals like Puncturevine, the pre-emergent application should occur in the early spring when soil temperatures consistently reach 50 to 55 degrees Fahrenheit. Conversely, winter annuals such as Lawn Burweed require a fall application, typically in late September or early October, before cooler soil temperatures trigger germination. Common active ingredients include Prodiamine, Pendimethalin, and Isoxaben, which provide effective control against annual weed species. A single application typically lasts eight to twelve weeks, and applying before any soil disturbance, such as aeration, ensures the protective barrier remains intact.