Sand vine is a perennial, vigorous, aggressive climber covering fences and shrubs. Flowers are in round clusters on stalks from the leaf axils. Flowers white, tiny, strongly scented; the corolla lobes stand upright around a fleshy corona. Blooms July–September. Leaves heart-shaped to triangular, opposite, to 3 inches long. Unlike many other milkweeds, sand vine has clear, watery (not milky) sap. Fruit a large, tapering pod, circular in cross-section (not angled or ridged) (sand vine has confusingly been called angle-pod in the past); seeds are attached to tufts of white, silky hairs and are released in late winter or early spring.
Similar species: Other Missouri milkweed vines have milky sap. Angle-pod (Gonolobus suberosus), found mostly in the Bootheel, has oval leaves with heart-shaped bases, angled (ridged) pods, and yellowish flowers with spreading corolla lobes. Our 2 climbing milkweeds in genus Matelea resemble angle-pod vegetatively, but the pods are covered with slender, warty projections (not angled).
Stem length: to 33 feet.
Common in northern and eastern Missouri, scattered in the remainder of the state.
Habitat and Conservation
Occurs in bottomland forests, banks of rivers and streams, and margins of ponds and lakes; also in cultivated and fallow fields, gardens, yards, fencerows, thickets, railroads, roadsides, and other disturbed areas. This plant establishes a complex, deep root system and is dispersed by wind-borne seeds, which fly from the milkweed pods on silky “parachutes” and can go anywhere the wind blows. They are also distributed by floating on water.
Status
Often considered a noxious weed, this native vine itself becomes a valuable miniature habitat for native insects. Many butterflies, bees, wasps, and others drink nectar from the flowers, but one commonly also sees clusters of yellow-orange aphids drinking sap from the stems. They, in turn, draw ladybird beetles and other predatory insects, which feast upon them. Many of these insects are preyed upon by birds, spiders, and more.
Human Connections
Beloved by bees, butterflies, and other insects for its nectar, sand vine is a problem weed of crop fields and gardens, where it can be difficult to eradicate. Some do cultivate it as an ornamental and as a native plant in butterfly gardens, and beekeepers value it as an excellent honey plant.
Ecosystem Connections
This native milkweed vine provides needed nectar for monarch butterflies as they migrate southward in late summer. Monarchs also lay their eggs on the plant, and their larvae feed on the foliage. Doing so, they ingest toxic milkweed chemicals that, in turn, make the insect toxic to its predators.