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Dioscorea villosa is often confused with:
Dioscorea polystachya
Plants that fill a similar niche:
Cocculus carolinus
Phlox glaberrima
Vitis vulpina

Dioscorea villosa

Previously known as:

  • Dioscorea quaternata
  • Dioscorea quinata
  • Discorea villosa var. hirticaulis
  • Merione villosa
Phonetic Spelling
dy-oh-SKOR-ee-uh vil-OH-suh
Description

Wild yam is a native, herbaceous perennial, and twining vine that grows 3 to 18 feet long and is found in moist forests and woodlands in Southern Ontario to the Central and Eastern United States. It has smooth, cylindrical, twining stems, green cordate leaves with palmate veining, and male and female flowers on separate plants. It is a member of the yam family (Dioscoreaceae).  The genus name, Dioscorea, honors a Greek physician and botanist, Pedanios Dioscorides. The specific epithet, villosa, means covered with soft hairs. This refers to the presence of soft hairs on the undersides of the plant's leaves.

Grows in full sun or partial shade and in various soil types.

The distinctive features of the wild yam include the palmately veined leaves, tiny flowers arranged in racemes or panicles, a 3-angled seed capsule, and slender rhizomes. The leaves are cordate, smooth, and medium green, and their petioles are green to dark red. Individual plants have either male or female flowers, and the flowers develop at the leaf axils. The male flowers are in 4 to 12-inch-long panicles, and the female flowers are arranged in 3 to 8-inch racemes. The tiny male flowers are 1/8-inch across, each having 6 whitish-green or yellowish-green tepals, 6 fertile stamens, and appear in clusters of 1 to 3 blooms. The tiny female flowers are similar except they have 5 to 15 blooms per raceme, 6 infertile stamens, and a large ovary. The female flowers are replaced by 1-inch capsules, each capsule containing 1 or 2 seeds.

The wild yam can be found in woodland borders, thickets, near railroad clearances, or fences. The vines can provide habitat for birds; however, mammals tend to avoid the leaves as a food source.

Insects, Diseases, and Other Plant Problems:  No significant insect pests or diseases.

See this plant in the following landscape :
Cultivars / Varieties:
Tags:
#showy leaves#NC native#twining#dioecious#rhizomes#herbaceous vine#herbaceous perennial#native vine#food source fall#food source herbage#Piedmont Mountains FAC#Coastal FACW#vine#perennial vines#Audubon#perennial#sun#climbing plant
 
Cultivars / Varieties:
Tags:
#showy leaves#NC native#twining#dioecious#rhizomes#herbaceous vine#herbaceous perennial#native vine#food source fall#food source herbage#Piedmont Mountains FAC#Coastal FACW#vine#perennial vines#Audubon#perennial#sun#climbing plant
  • Attributes:
    Genus:
    Dioscorea
    Species:
    villosa
    Family:
    Dioscoreaceae
    Uses (Ethnobotany):
    Has been used medicinally, but it reportedly can cause kidney damage.
    Life Cycle:
    Perennial
    Recommended Propagation Strategy:
    Division
    Country Or Region Of Origin:
    Southern Ontario to Central and Eastern United States
    Distribution:
    Native: AL, AR, CT, DC, DE, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, MI, MN, MO MS, NC, NE, NJ, NY, OH, OK, PA, RI, SC, TN, TX, VA, VT, WI, WV; Ontario. Introduced: Cuba and the Leeward Islands.
    Wildlife Value:
    It provides nesting and cover for birds and some small animals.
    Play Value:
    Textural
    Wildlife Cover/Habitat
    Climbing Method:
    Twining
    Edibility:
    The wild yam does not produce edible tubers.
  • Whole Plant Traits:
    Plant Type:
    Herbaceous Perennial
    Native Plant
    Vine
    Habit/Form:
    Climbing
    Maintenance:
    Low
    Texture:
    Medium
  • Cultural Conditions:
    Light:
    Full sun (6 or more hours of direct sunlight a day)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    Loam (Silt)
    Sand
    Soil pH:
    Alkaline (>8.0)
    Neutral (6.0-8.0)
    Soil Drainage:
    Good Drainage
    Moist
    Occasionally Dry
    Available Space To Plant:
    12 inches-3 feet
    NC Region:
    Coastal
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
  • Fruit:
    Fruit Color:
    Cream/Tan
    Gold/Yellow
    Green
    Display/Harvest Time:
    Fall
    Fruit Type:
    Capsule
    Fruit Length:
    < 1 inch
    Fruit Width:
    < 1 inch
    Fruit Description:
    The fruit is an ovoid, 3-celled capsule, each cell contains 2 seeds (occasionally only 1), and each capsule measures about 1 inch long. The capsule ripens to a golden green, and the fruit is displayed from September to November. The capsule becomes tan and paper-like over the winter. The seeds are flat, winged, and carried by the wind.
  • Flowers:
    Flower Color:
    Gold/Yellow
    Green
    White
    Flower Inflorescence:
    Panicle
    Raceme
    Flower Bloom Time:
    Spring
    Summer
    Flower Size:
    < 1 inch
    Flower Description:
    Each plant consists of either all male or all female flowers. Greenish-yellow flowers bloom from April to July. Flower inflorescence differs between male and female plants. The male flower is about 1/8 inch across and has 6 greenish-white or yellowish-green tepals. The male flowers are arranged in small clusters or cymes of 1 to 3 blooms and are on drooping panicles about 4 to 12 inches long, and are found at the leaf axils. The female flower is about 1/8 inch across and 1/3 inch long with 6 greenish-white or yellowish-green tepals and a large ovary. The female flowers appear in drooping spike-like racemes of 5 to 15 flowers, and the racemes measure 3 to 8 inches long.
  • Leaves:
    Leaf Color:
    Green
    Leaf Value To Gardener:
    Showy
    Leaf Type:
    Simple
    Leaf Arrangement:
    Alternate
    Leaf Shape:
    Cordate
    Leaf Margin:
    Entire
    Hairs Present:
    Yes
    Leaf Length:
    3-6 inches
    Leaf Width:
    1-3 inches
    Leaf Description:
    The leaves are arranged in an alternate pattern except near the base of the vine, where they can be opposite or whorled. The leaves are cordate, measure 2 to 4 inches long and 1.5 to 3 inches wide with entire margins, and have 7 to 11 veins per leaf and are palmately veined. The upper surface is smooth and medium green, and the lower surface has fine to dense short hairs and is pale green. Young leaves are a golden green. Its petioles are light green to dark red, smooth, and measure 1.5 to 6 inches long. The leaves hang down from the petioles.
  • Stem:
    Stem Color:
    Gold/Yellow
    Green
    Red/Burgundy
    Stem Is Aromatic:
    No
    Stem Cross Section:
    Round
    Stem Surface:
    Smooth (glabrous)
    Stem Description:
    The stems are slender, smooth, cylindrical, twining, and vary in color from light green to pale yellow to reddish-green or dark red.
  • Landscape:
    Landscape Location:
    Woodland
    Landscape Theme:
    Native Garden