Securigera varia, Crownvetch


Invasive Species: Securigera varia, Crownvetch

Crownvetch is a low-growing, invasive, herbaceous vine that usually forms thickets up to 3 ft. (0.9 m) in height. The leaves are pinnately compound with 9 to 25 pairs of leaflets and a terminal leaflet. Leaflets are 0.75 in. (1.9 cm) long. Flowering occurs in the summer. The fragrant, pea-like flowers are white to pink to purple and resemble a large clover flower. Crownvetch reproduces and spreads rapidly by rhizomes as well as seeds. …

Clematis terniflora, Sweet Autumn Virginsbower


Invasive Species: Clematis terniflora, Sweet Autumn Virginsbower

Sweet autumn virginsbower is an invasive climbing, semi-evergreen, ornamental vine. The leaves are opposite, compound (with three to five leaflets), and the margins are entire. Leaflets are each 2 to 3 in. (5 to 7.6 cm) long. White, fragrant, four-petaled flowers appear in the late summer through the fall. Seeds are also showy, and production is prolific. Seed heads have long, silvery-gray, feather-like hairs attached. The native species (C. virginiana) …

Cynanchum louiseae, Black Swallowwort


Invasive Species: Cynanchum louiseae, Black Swallowwort

Black swallowwort is an invasive herbaceous, twinning, perennial vine. Leaves are opposite, dark green, oval, shiny, entire, 3 to 4 in. (7.6 to 10.2 cm) long, and 2 to 3 in. (5.1 to 7.6 cm) wide. Flowering occurs in June to July when dark purple, five-petaled, star-shaped flowers appear in clusters. Flowers are approximately 0.25 in. (0.6 cm) across and covered with white hairs. Fruit are pods, similar to milkweed pods, which are …

Humulus japonicus, Japanese Hop


Invasive Species: Humulus japonicus, Japanese Hop

Japanese hop is an invasive¬†annual, climbing or trailing vine that is native to eastern Asia. This vine has five-lobed leaves (generally), downward pointing prickles on the stem and bracts at the base of the petioles. Leaves are opposite, rough, 2 to 5 in. (5 to 13 cm) long, five- to nine-lobed with toothed margins. Most leaves will have five lobes, but the upper leaves may only have three. Flowers originate in the …

Dioscorea alata, Winged Yam


Invasive Species: Dioscorea alata, Winged Yam

Winged yam is an invasive herbaceous, twining vine that can grow to lengths exceeding 30 ft. (9.1 m). It invades open to shady areas in the extreme southeastern United States. Leaves are opposite, 8 in. (20.3 cm) long, and narrowly heart-shaped with long petioles. The stems are square with the corners compressed into wings. The vine rarely flowers. The seeds are winged all around. The chief means of reproduction is by aerial potato-like …

Vinca minor, Common Periwinkle


Invasive Species: Vinca minor, Common Periwinkle

Common periwinkle, a common invader throughout most of the United States, is an evergreen to semievergreen trailing vine that reaches up to 6.6 ft. (2 m) in length. Vines can reach a height of 6 in. (15.2 cm). The stems are slender, somewhat woody, and green. The opposite, glossy leaves are approximately 1 in. (2.5 cm) long and narrowly elliptical. Some varieties have variegated leaf colors. Flowers are violet to blue (possibly white), …