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Thursday - September 21, 2006

From: Midland, TX
Region: Southwest
Topic: Vines
Title: Control methods for Tribulus terrestris, Goatheads or Puncturevine
Answered by: Joe Marcus and Nan Hampton

QUESTION:

We have some land that has so many goatheads we can't do anything with it. We would like to know what if anything will remove them from our place. There has to be something out there that will kill these goatheads out. REALLY BAD HERE. Thank you.

ANSWER:

Goathead (aka Puncturevine), Tribulus terrestris is a pernicious weedy introduction from Europe which now has nearly global distribution. It is a member of the Caltrop family, Zygophyllaceae. Both the common family name, Caltrop, and the genus name, Tribulus, refer to a particularly wicked iron weapon of ancient origin known as a caltrop used to incapacitate horses, other war animals and foot soldiers.

Puncturevine prefers and thrives in disturbed soils, especially over-grazed land. Improved land management is often the first and best step to take in controlling the weed. An annual plant, it does not compete well with other plants, especially turf grasses. If overgrazing or missing, groundcovering plants are not the issue on your land, there are other control strategies available.

If the amount of land affected is small, removal by hand is probably your best control method. It is best to remove the young plants by hand-pulling, hoeing or tilling before they go to seed. Since your plants are already producing seeds, you should pull, hoe or chop out the existing plants, rake or sweep up the spiney fruits, go over the soil with a piece of scrap carpet, rug or other nappy cloth and burn everything you pick up.

Other control methods include the use of introduced weevils and burning with propane torches. Both methods will likely yield much less than complete control, but may make sense if you're dealing with large acreage. Your county agricultural extension service agent may also be able to help as others in your area are dealing with the same pest.

Finally, we are including some links here for much more information about Goatheads:
Texas A&M's Toxic Plant Database
The UC Davis, IPM Online website
The Washington State Noxious Weed Control Board website
The California Department of Food and Agriculture Weed Information website
The North Dakota Department of Agriculture Invasive Species Manual

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Thursday - September 21, 2006

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