Flower:

Few to numerous round to hemispheric flower clusters 1 to 2 inches across, each on a long stalk and containing up to 100+ flowers (usually 25 or more), with male and female flowers on separate plants (dioecious). Flowers are about ¼ inch across with 6 green to yellow-green tepals (petals and similar sepals). Female flowers have 6 sterile stamens (staminodes) surrounding a green, round ovary with a 3-parted style at the tip.

Male flowers have 6 creamy white to pale yellow-tipped stamens. Both male and female clusters arise singly from the leaf axils all along the stem, starting with the lowest leaf. A flower stalk is usually longer than the associated leaf stalk, sometimes significantly so.

Leaves and stems:

Leaves are alternate, 1½ to 3+ inches long, 1 to 2½ inches wide, egg-shaped to nearly round, rounded to blunt to pointed at the tip, heart-shaped to rounded to straight across at the base, on a stalk that is usually shorter than the blade. The upper surface is hairless, the lower sparsely short-hairy. Edges are toothless though may be somewhat crinkly or wavy. Leaves become smaller as they ascend the stem, though the lowest leaves are somewhat smaller than those mid-stem.

Leaves along most of the stem typically have a pair of long tendrils at the base of the stalk; these tendrils twine around supporting vegetation and enable the plant to climb. Stems are branched, hairless, erect to ascending, or more sprawling when supporting vegetation is not available.

Fruit:

Fruit is a round berry 1/3 inch or so in diameter that ripens from green to purplish-black, covered with a waxy coating.

Notes:

Blue Ridge Carrion Flower is one of the larger Minnesota Smilax species, though young plants are easily confused with both Upright Carrion Flower (Smilax ecirrhata) and Illinois Carrion Flower (S. illinoensis), and all 3 may grow together which makes it more challenging. S. lasioneura is probably the most variable in leaf shape, number of flower clusters and number of flowers in a cluster, but, unlike the other two species, it has a branched stem and many tendrils that twine around itself and other vegetation. Its leaf stalks are mostly shorter than the blade and flower stalks are mostly longer than the leaf stalks, sometimes significantly so. While a robust plant may grow to 8 feet long and have numerous flower clusters, a 3-foot plant will more closely resemble the other two.

By comparison, neither S. ecirrhata nor S. illinoensis has a branching stem and both have few or no tendrils. S. ecirrhata also has only 1 to 3 flower clusters that are usually all below the leaves, fewer than 25 flowers per cluster, and has fewer than 20 leaves per plant, often less than 10. S. illinoensis leaf stalks are mostly as long as or longer than the blade and flower stalks are shorter (i.e. opposite of S. lasioneura). A fourth species, Bristly Greenbrier (S. tamnoides or S. hispida), is the only Smilax species in Minnesota with a prickly stem.

Of note is we spent a number of years agonizing over some of these Smilax species. The DNR and Bell Herbarium both list Smooth Carrion Flower (Smilax herbacea) as present in Minnesota, but this appears to be untrue, though may go back to a time when S. lasioneura was treated as a variety of S. herbacea (var. lasioneura) and old records were not updated when the taxonomy was. Over the years we inspected countless leaves looking for a hairless plant, only to discover every Smilax plant in Minnesota has hairy leaves. Adding to the confusion was the number of flowers in a cluster. In Houston County we came upon a robust plant we were sure was S. herbacea because we counted about 100 flowers in a cluster, which should have eliminated S. lasioneura as a contender since multiple references state it should only have up to 35. Those references are simply wrong. We were never sure of what we had until we conceded that S. herbacea was indeed not present in the state and Michigan Flora's Smilax key was more accurate. It became easier after that, but they can still be a difficult group.

S. lasioneura is sometimes misspelled Smilax lasioneuron.