Stem

Prostrate; multiple stems that spread radially from crown; up to 3 ft. long (sometimes longer); highly branched, green to reddish-brown and often hairy

Leaves

Opposite, usually hairy, pinnate-compound, 1-2 in. long, with 3-7 pairs of leaflets; leaflets oval and 0.2-0.6 in. long; edges (margins) are smooth

Flower

Yellow, 0.2-0.6 in. diameter, with 5 petals; arise from leaf axils
Fruit is a woody bur that breaks into 5 sections (nutlets) at maturity; each nutlet has 2 stout, spines and contains 3-5 seeds

Root

Slender, deep taproot; can associate with nitrogen-fixing bacteria

Other

Often found in still or slow-moving water; not known to occur in Nevada
Annual; reproduces by seed
Also known as goathead, Mexican sandbur, Texas sandbur and tackweed; spines on fruit can cause injury to livestock and humans and can also puncture tires; foliage can be toxic to livestock

Control

Frequent hand-removal or tillage prior to seed production
Two insect biological control agents are available
Apply 2,4-D, dicamba, glyphosate, imazapic or picloram to young, actively growing plants; chlorsulfuron or imazapyr preemergence or early post emergence

Blecker, L., Creech, E., Dick, J., Gephart, S., Hefner, M., Kratsch, H., Moe, A., Schultz, B. 2020, Nevada Noxious Weed Field Guide – Puncturevine, Extension, University of Nevada, Reno, Field Guide

Learn more about the author(s)

Heidi Kratsch

Also of Interest:

Nevada Noxious Weed Field Guide – Puncturevine