Native to: East Africa, Madagascar, Mascarene Islands
Because of its tolerance to salt and drought conditions, it has been used extensively as a groundcover in coastal landscapes in the U.S., particularly Florida. Its common name, puncture vine, comes from the spiny fruits that are produced, which are an unwelcome ‘thorn’ in the side of many bicyclists, gardeners, and animals. The fruits are sharp enough to puncture tires and are very painful to step on. It has medicinal uses, treating ailments such as headache, nervous disorders, and constipation.
Habit: Perennial (sometimes annual) herb, with many-branched trailing stems to 1 m long or longer. Tap root woody, stems often slightly woody at base, tips erect, younger stems covered with silky hairs.
Leaves: opposite, to 10 cm long, even-pinnate. Leaflets in 5-8 pairs, elliptic or oblong, to 2.8 cm long and 1.2 cm wide, covered with silky hairs, margins entire, bases rounded, tips bluntly pointed. Terminal leaflet pair spine tipped. Stipules linear, to 0.7 cm long.
Flowers: showy, solitary in leaf axils, on long, hairy stalks 2 to 3 cm long, sepals 5, lance shaped, petals 5, bright yellow, rounded, to 2.5 cm long.
Fruit/Seeds: hard spiny capsule, burr-like, to 1.5 cm across, splitting into 4 or 5 segments, each of which has two sharp spines to 8 mm long and contains one or more seeds.
Distribution in Florida: South and Central
Seeds are spread easily via machinery, animals, and humans and are very persistent in the environment, able to remain dormant in the soil for up to 5 years. Puncture vine invades dunes, coastal lands, sandy sites, median strips, and disturbed sites. Human and animal harm caused by spiny fruits is also of concern.
Do not plant. Decontaminate equipment, gear, and clothing when leaving infested areas.
Replace in landscape with native plants. Can be controlled by pulling them out of moist soil, be sure to wear gloves to protect your hands from the prickly fruits.
Mowing is not effective due to the prostrate growth habit.
There are two biological control agents that have been used with limited distribution in other areas.
Glyphosate and dicamba have been used with excellent results. 2,4-D also shows good results. A 1-2% solution of each of these with surfactant is recommended. Certain pre-emergent herbicides can kill puncture vine seedlings as they germinate, but their utility may be limited in natural areas due to soil persistence. Consult your local UF IFAS Extension for further assistance with management recommendations.