Smilax bona-nox L.
Family - Smilacaceae
Habit - Rhizomatous perennial vine, dioecious.
Stems - To 8 m, woody, climbing, glabrous or with stellate hairs, armed with spines.
Stem and tendrils.
Leaf - Alternate, numerous, to 11 cm long, simple. Petioles shorter than leaf blades, often with tendrils present. Leaf blades broadly ovate, at least some usually fiddle-shaped, the margins thickened, often with sparse white, spinelike projections, otherwise entire, the undersurface not much paler than the upper surface, glabrous, the network of smaller veins raised and thickened on the undersurface.
Inflorescences - Axillary umbels in upper leaves, the peduncle 1-5 times as long as the petiole of the subtending leaf. Umbels mostly with 8-20 flowers.
Flowers - Flowers with 6 tepals in 2 series, these 3-5 mm long, green to yellowish green. Staminate flowers with 6 stamens, these free or fused at the filament bases. Pistillate flowers with 1 superior ovary with 3 locules, the style absent or very short, the stigmas 1 or 3, spreading.
Fruits - Berries, 6-8 mm in diameter, black, usually not glaucous.
Flowering - May - June.
Habitat - Forests, edges of bluffs and glades, fencerows, old fields, often climbing in thickets.
Origin - Native to the U.S.
Other info. - This vine is found throughout the southern third of the state. Species of Smilax can be difficult to identify reliably. A good indicator for S. bona-nox is the presence of at least a few strongly fiddle-shaped leaves, often with mottling on the upper surface. The stems are armed with sharp spines, though these are sometimes sparse.
Photographs taken at Allred Lake Natural Area, Butler County, MO, 5-19-2014 (SRTurner).