Woe to the gardener who finds goat head weed (puncture vine) growing among desired plants or in a lawn. This annual weed grows easily in areas where there is little healthy competition with desired plants. The puncture vine name aptly describes the seeds of this obnoxious weed because the seeds are sharp enough to puncture through shoe soles, bicycle tires and the feet of animals and people. Tackle goat head weed removal when you find this weed growing in your landscape to preserve your growing areas.
Spray either herbicide product over the goat head weed while the plant is actively growing and thriving and before it blossoms. Use glyphosate in an area where other desirable plants or grasses do not grow nearby. When goat head grows in a lawn, use the 2,4-D herbicide spray instead because this herbicide spray will not harm grass but will eradicate only the broadleaf weeds. Spray either herbicide spray on a day when temperatures range between 60 F and 80 F and you expect no rain. Saturate the foliage completely with the herbicide spray.
Dig up any goat head weed plants you find growing with the trowel. Take care to remove the entire root system as well and the above-ground foliage. You must gather every spiny seed as well to prevent the seeds from germinating. Place all the plant parts into the plastic bag and discard the bag into the trash (do not compost the plant remains--they will germinate easily in a compost bin).
Check diligently for new goat head weed emergence throughout the growing season. To eradicate this weed completely, you may need to apply the herbicide spray or pull up the weeds manually every three weeks throughout the entire season. Successful eradication depends upon removal of every seed (the seeds can survive for many years before they eventually germinate).