The term “goat heads” refers to the highly noxious burrs produced by the puncture vine, Tribulus terrestris, an invasive annual weed. These pea-sized fruits harden into woody, spiny structures, typically splitting into five segments, each bearing two to four sharp spines up to 10 millimeters long. The hardened spines are strong enough to puncture bicycle tires and cause painful injuries to skin and paws. Physical removal of these burrs and the parent plants is the most immediate and effective way to mitigate the hazard and halt the spread of this tenacious weed.
Essential Safety and Preparation
Handling this sharp debris requires specific personal protection. Puncture-resistant footwear, such as thick-soled work boots, is advised, as the burrs can easily penetrate thin shoes or sandals. Heavy-duty gloves, ideally made of thick leather or reinforced synthetic material, must be worn when pulling plants or collecting the burrs by hand.
After working in an infested area, conduct a thorough check of clothing and equipment. Burrs adhere easily to fabric and can be tracked indoors, leading to new infestations or injuries. For pet owners, carefully inspect the animal’s paws and fur before they enter the house. Pay particular attention to the soft webbing between the paw pads, where the burrs often lodge. A coarse doormat or shoe tray can help contain burrs scraped off footwear.
Low-Tech Manual Collection Methods
For small, contained areas or spot cleanup, several low-tech strategies are effective for gathering scattered burrs. A common method involves using a piece of sacrificial material, such as an old towel, carpet remnant, or thick blanket. This material is dragged across the contaminated surface, allowing the sharp spines to embed themselves in the fibers.
Once the material is saturated with burrs, it should be folded, spiny side inward, and sealed in a puncture-proof container for disposal. Duct tape offers a precise, handheld tool for removing individual burrs, especially those stuck in crevices or gravel. Wrapping a hand in the tape, adhesive side out, allows for quick manual pickup of localized clusters.
To remove the entire Tribulus terrestris plant before it drops more seeds, a sturdy hand tool is necessary to sever the deep taproot. A small trowel or sturdy knife can cut the root a few centimeters below the soil surface, ensuring the whole plant is removed. Removing the entire plant body, especially when the soil is moist, is more effective than simply pulling the trailing vines. This manual approach should be applied repeatedly throughout the growing season to catch new seedlings before they mature and produce new burrs.
High-Volume Mechanical Removal Techniques
When dealing with larger infestations across driveways, yards, or gravel areas, mechanical techniques are necessary to clear the surface debris. Specialized tools known as burr or goathead rollers are commercially available. These devices use a metal drum covered in a durable, textured fabric that lifts and collects the spiny burrs as the roller is pushed or pulled across the ground.
The design of these rollers allows them to gather high volumes of burrs from various surfaces, including grass, dirt, and gravel. For larger acreage, an ordinary pull-behind lawn sweeper can be modified or used in conjunction with other methods. Users report success by first dragging a piece of heavy carpet or a blanket behind an ATV or mower to embed the burrs, then using the sweeper to collect the debris-laden material.
A wet/dry shop vacuum can be a useful mechanical tool for clearing burrs from small, confined areas like concrete patios or gravel borders. When using a vacuum, it must be a heavy-duty model with sufficient power to ingest the sharp, dense debris without tearing the internal filter or collection bag. Because the burrs are abrasive, using a model designed for construction or workshop cleanup is recommended over a standard household vacuum cleaner. In all mechanical removal, the goal is to lift the burrs without disturbing the soil, which could bring dormant seeds to the surface and trigger new germination.
Proper Disposal to Prevent Recurrence
The correct disposal of all collected plant material and burrs is essential for preventing future infestations. Tribulus terrestris seeds are persistent, maintaining viability in the soil for an estimated three to six years. Collected material cannot be placed in a compost pile, as composting rarely generates enough sustained heat to destroy the seeds within the woody burrs.
All burrs and plant matter must be sealed in heavy-duty, puncture-resistant plastic bags, which may require double-bagging to prevent the spines from tearing the material. These bags should be disposed of through a municipal waste service that directs the material to a landfill or a facility equipped to handle noxious weeds. For an added layer of security, the sealed bags can be left exposed to direct sunlight for several weeks in a process known as solarization.
Solarization uses solar energy to raise the temperature inside the bag high enough to sterilize the contents, effectively killing the seeds. Placing the sealed bags in a sunny location for at least four to six weeks during the hottest part of the year ensures the seeds are rendered non-viable before the bags are sent to the landfill. This disposal step significantly reduces the seed bank in the environment.