General Control Strategy
Puncturevine spreads by seed so controlling plants prior to seed production is critical to prevent further seed entering the seedbank. When working in puncturevine infestations, make sure to clean shoes, clothing and tires to prevent spreading seeds to other areas. Use any of these, or a combination of these methods to control puncturevine. After puncturevine control, plant areas with site appropriate plants to provide competition and reduce further puncturevine invasion.
Mechanical Control
Puncturevine can be hand-pulled or controlled by hoeing or digging up, ideally prior to seed formation in the spring. If plants have already produced seeds, make sure to remove all possible spiny burrs from the ground. Make sure to wear gloves when removing puncturevine and be careful of the sharp spines. Shallow tilling, 1 inch or less, can also be used on small plants in the spring to control the plant prior to flower and seed development. Tilling deeper in the soil may just bury that will survive longer. All methods will need to be repeated as new seeds germinate during the year and for at least four years due to seed viability. Continue to monitor and control as needed. Mowing is ineffective due to the plant’s low growth form.
Herbicide Control
Appropriate herbicide use can provide effective control of puncturevine. After the plants have emerged from the soil, and before the plants develop seeds, postemergent products are effective. The smaller or younger the plant, the better the postemergent herbicides work. Make sure to treat plants before they develop seeds. When choosing a soil applied chemical for puncturevine control, consider whether a selective or non-selective product is needed. Always read the label instructions before applying any herbicides for proper rate and timing. Use chemicals that are compatible with your goals. So, all of that out of the way, you can use a broadleafed weedkiller (containing 2,4-D) to eliminate goatheads at any time that you see them growing actively, preferably earlier in the growing season than August.

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