English ivy (Hedera helix)
Eurasian, not English, in origin, this evergreen vine threatens habitats at all heights. At ground level, its leaves shade out seedlings and herbs, forming acres of monoculture and attracting rodents. In trees, it engulfs branches, shading and slowly killing them. Its weight topples trees in wind, snow or icy conditions. It serves as a reservoir for bacterial leaf scorch, a serious disease of trees including maples, oaks and elms. Vines mature in trees, then flower and bear toxic berries which induce birds to vomit them out, ensuring spread. Any rooted piece can resprout. Waxy leaves repel herbicides. Sprays must be applied in high concentrations and with a spreader-sticker. P/D, F/S, SM, C/M/reC, PostE, C&P/S - see key below
Japanese honeysuckle vine (Lonicera japonica)
Introduced for ornamentation and for erosion control, its rich fragrance and drops of June nectar have endeared this vine to many. Because deer ignore it and, possibly because high CO2 levels are invigorating vine growth, this vine has become highly invasive. A sun lover, it creates dense monocultures on the ground. Spiraling up trees or shrubs, it strangles and kills by blocking sunlight. Its weight fells weakened trees. Evergreen foliage continues growth throughout the year. It flowers from spring to fall, producing black berries. P/D, C/M/reC, C&P/S - see key below
Kudzu (Pueraria montana var. lobata)
“The vine that ate the South” was promoted as livestock forage, an ornamental, and erosion control until the 1950s. Its incredible growth rate of one foot a day and 60 feet a season, plus a root system up to 400 lbs, make this invasive unequaled. Pods produce some viable seed, but reproduction is primarily vegetative. As many as 30 shoots grow from a single crown and can root where nodes touch soil. Control methods such as cutting and mowing must continue for two seasons or more. Penned goats can exhaust the root system by grazing. Herbicides are most effective in early fall. C/M/reC, C&P/S - seekey below
Mile-a-minute vine/devil’s tear thumb (Polygonum perfoliatum)
This barbed annual vine, native of Asia, can grow 25 feet a season in sun or shade. Bright blue berries are spread widely by birds. It quickly shades and smothers plants. It has almost no root system, so pulling it is easy. Release of an insect which feeds exclusively on mile-a-minute should slow, though not eliminate, this invasive in the future. P/D, F/S, PostE - see key below
Oriental bittersweet (Celastrus orbiculatus)
This Asian vine has almost entirely replaced native American bittersweet by out-competing and hybridizing with it. Thick woody vines engulf and smother trees, while their weight can topple them. Orange berries are spread by birds and human admirers that plant it or use berries in decorations. Leaves are round on young growth and more pointed on older plants. Orange-red roots provide fast identification when pulling the myriad seedlings that pop up under trees and shrubs. Roots can sucker, and stems can root where they touch the ground. P/D, F/S, C/M/reC, C&P/S - see key below
Porcelainberry (Ampelopsis brevipedunculata)
Introduced for its multicolored berries, this woody Asian vine climbs over shrubs and trees, shading and killing them. Leaves resemble grape leaves, but bark does not peel whereas grape-vine bark does peel. It invades full-sun or semi-shade areas with moist, not permanently wet, soils. P/D, C&P/S - see key below
Vinca/periwinkle (Vinca minor)
Periwinkle provides evergreen foliage, quick growth, and lilac-to-white flowers in spring. A popular groundcover, it has escaped to natural areas where it crowds out wildflowers and other herbaceous natives. It spreads vegetatively by rooting at nodes and tips, and from root pieces. It is appropriate in the home landscape, ONLY when growth is monitored and kept far from natural areas. P/D, C/M/reC, C&P/S - see key below
Wavyleaf basketgrass, (Oplismenus hirtellus ssp. undulatifolius)
This Eurasian grass is a bright green shade perennial,which engulfs forest floor plants in a solid mat. Its widebladed leaves alternate along low-lying stems. Leaves are very unusual with leaf ripples like a flag in the wind. Stems are noticeably hairy (unlike native basketgrass species) and root where nodes touch soil. In fall, seeds with sticky tips attach to passing animals and humans. P/D, PostE - see key below
Wintercreeper/creeping euonymus (Euonymus fortunei)
As a groundcover, this evergreen vine forms dense mats on the ground, excluding low native plants. It also climbs trees. Tolerant of good or poor soils and sun to dense shade, it spreads vegetatively and by berries. Not appropriate as groundcover. P/D, F/S, C/M/reC, C&P/S - see key below
Wisteria—Chinese and Japanese (Wisteria sinensis, W. floribunda)
With showy fragrant panicles of lavender bloom, this ornamental has been planted extensively. Escaped to natural areas, its woody vines strangle and shade out foliage, killing trees. It reproduces from seeds in fuzzy pods, from stems touching the ground, and from any bit of root left in the ground. Cut vines must be bagged and disposed of so no portion touches the ground. After cutting at ground level, woody vines must be unwrapped from tree trunks or they will still girdle trees. P/D (young), F/S, C/M/reC, PostE, C&P/S, WW - see key below
Key for control methods
- (B) Burn: Use controlled fires to destroy aboveground growth. (First, contact local fire department).
- (C&G) Cut and grind: Cut down, then grind stump.
- (C/M/reC) Cut, Mow, and Re-cut: Cut to the ground and re-cut at the first appearance of new growth. This starves the root system. It may require persistence.
- (F/S) Flower/Seed removal: Do not allow seed development. When plant removal must be postponed, prevent spread by seed. Cut off flowers before seed forms. Some plants flower and produce seed at the same time. Bag and dispose of seeds in landfills. DO NOT compost.
- (G) Girdle: Remove bark and cambium layer. Remove (or spray) any re-sprouting from roots or below girdled area.
- (P/D) Pull/Dig: This is especially effective with seedlings or annuals. Mile-A-Minute vine, for instance, has almost no root system at all. However, for those that can re-sprout from a tiny root piece, such as Canada thistle, removal of entire root is critical. Moist soil facilitates.
- (SM) Smother: Cover plants with cardboard, many layers of newspapers, or plastic, then mulch. Plastic must be removed afterward, and if mulch decomposes on it, this can be an arduous process.
- (WW) Weed Wrench (TM): This tool can uproot large shrubs and small trees
- (C&P/S) Cut and Paint or Spray: Cut down trunk and paint or target spray the stump within five minutes.
- (H/S) Hack & Squirt: Slash bark using a saw or hatchet, and squirt liquid herbicide into the wounds; re-spray any re-growth.
- (PostE) Post-emergent herbicides: Spray foliage of perennial/woody plants. Spot-treat in lawns.
- (PreE)Pre-emergent herbicide: Spread this granular herbicide prior to seed germination.