Tribulus terrestris


Family: Zygophyllaceae

Other Common Names: caltrop, goathead, cat's-head, devil's thorn
Weed class: B
Year Listed: 1988
Native to: Africa, Asia, Australia and Europe
Is this Weed Toxic?:


Why Is It a Noxious Weed?

Puncturevine is a toxic plant and a serious weed in pastures, roadsides, waste places and cultivated fields. The spines of the fruit can cause damage to animals and people. It’s a problem to the fruit pickers when growing in orchards or vineyards.

How would I identify it?

General Description

Puncturevine is an annual herb growing flat along the ground, from a simple, woody taproot. The fruit is a woody burr with sharp, rigid spines (strong enough to puncture bicycle tires or penetrate shoe soles).

Flower Description

The small, yellow flowers are borne on short stalks at leaf nodes. Flowers are solitary and have 5 petals, 5 sepals and 10 stamens.

Leaf description

Leaves are opposite, oblong and have short stalks.  They are 1 to 3 inches long and pinnately compound (having leaflets). Each leaflet is 1/4 inch long.

Stem description

Stems are numerous and up to 6 feet long. They form a dense mat.

Fruit Seed Description

The fruit is a woody burr with sharp, rigid spines.

Where does it grow?

Puncturevine is found in pastures, roadsides, waste places, parks, agricultural areas. Please click here to see a county level distribution map of puncturevine in Washington.

How Does it Reproduce?

Puncturevine reproduces by seed.

How Do I Control It?

General Control Strategy

Puncturevine spreads by seed so controlling plants prior to seed production will 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. 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, 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 can also be used in the spring to control the plant prior to flower and seed development. Mowing is ineffective due to the plant’s low growth form.

Cultural Control

Biological Control

The puncturevine seed weevil, Microlarinus lareynii, and the puncturevine stem weevil, Microlarinus lypriformis are two biocontrol agents that can provide good control when used together. The puncturevine seed weevil larvae destroy developing seeds and the adults can cause damage by feeding on stems, leaves, flowers and fruits. The puncturevine stem weevil larvae feed within the stems and root crowns and the adults feed on the stems and leaves. Both of these insects may have a harder time establishing in climates with cold winter temperatures.For more information about the biological control of puncturevine, please visit WSU Extension Integrated Weed Control Project.

Herbicide Control

Appropriate herbicide use can provide effective control of puncturevine. After the plants have emerged from the soil, postemergent, products are effective. The smaller or younger the plant, the better the postemergent herbicides work. 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. Please refer to the PNW Weed Management Handbook, or contact your county noxious weed coordinator.

For More Information

See our postcard for early detection information about puncturevine.

See our brochureon puncturevine.

See our brochure in Spanish on puncturevine.

See our Written Findings for more information about puncturevine (Tribulus terrestris).

Franklin County NWCB Fact Sheet on puncturevine

Stevens County NWCB Fact Sheet on puncturevine

Franklin County NWCB Brochure on punturevine and Bermuda grass

Control Options for puncturevine from Lincoln County NWCB

Additional Photos