Weeds

Goathead

(Puncture Vine, Caltrop, Yellow Vine)

Goathead
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This low-growing (2" to 4" tall) herbaceous perennial plant is well-known as "Puncture Vine" due to its stickers/thorns it produces. It is considered an annual plant in colder climates. The small (1/4" to 3/8"), 5-petaled, yellow flowers are borne from April to October. One week after the flower blooms, the fruit is formed and easily falls apart into 4 or 5 nutlets. These nutlets or seeds have two or three sharp thorns and resemble a goat's head or a bull's head. These spines are capable of inflicting significant pain to bare feet. The seeds will remain viable in the soil for a number of years. Cultivating the soil will bring dormant seeds to the surface and new plants will germinate. This plant has become naturalised in North America. In some states it is considered a noxious weed and invasive plant.