Other names: Goathead, caltrop, devil’s thorn
Life cycle: Summer annual
Found in: Cropland, pastures, roadsides, walkways, gardens and waste areas in the western U.S.
General description: Mat-forming plant with green to orange-brown, 1½ foot to 5 foot stems radiating from a root crown.
Seedlings: Cotyledons are green above and gray underneath, thick, oblong and brittle. Creased along the midvein.
True leaves: Four to eight pairs of oval-shaped leaflets arranged oppositely along the stalk and covered in tiny hairs.
Flowers and fruit: Flowers are single, bright yellow and bloom on short stalks near leaf bases. Fruit is a green, spiny and five-rayed bur that turns brown and woody and splits into five seedpods at maturity.
Special note: Puncturevine can be toxic to livestock and is considered noxious in 11 states.