Dan Tenaglia, Missouri Plants.com

Securigera varia (Coronilla varia)

Crown Vetch

Native Origin: Native to Central and Southern Europe, crown vetch was introduced by the U.S. Department of Agriculture in the 1950s for planting on slopes as erosion control. Widely used along roadways, it was seeded across the country during the expansive construction of the Interstate Highway system and its subsidiary roadway improvements. Crown vetch also produces high quality fodder for livestock –excepting horses, which can be poisoned by eating it in large quantities and for deer and elk. Since it aids nitrogen fixation in soil, crown vetch also has been planted for mine reclamation and as a green manure cover crop.

Ohio State Weed Lab Archive

Description, Habitat & Ecological Impact: A member of the Pea family, crown vetch has attractive blossoms, ranging in color from deep pink, to white, to violet, on umbels on long stalks. Flowering occurs from early summer into autumn with narrow, flattened seedpods produced. The dark green leaves as compound with nine to 25 leaflets per leaf. Crown vetch reproduces both by seed and vegetatively. Creeping stems can reach over six feet and rhizomes may grow to 10 feet long, enabling plants to quickly spread out and cover large areas. One plant can stretch out and cover between 70 to 100 square feet within four years.

Tolerant of a wide variety of growing conditions and soil types, crown vetch grows best and reproduces at high rates in open sunny sites. Natural areas, particularly prairies, glades and open woodlands, can be very quickly degraded by crown vetch as it out competes native grasses and flowers, turning once richly diverse plant and animal communities into a singly species desert. Crown vetch can and has successfully colonized and overtaken even well established tallgrass prairies. And, even after control measures reduce or eliminate crown vetch from an area, the natural soil processes and nutrient cycles remain altered due to the plants’ nitrogen-fixing capabilities.

Ohio State Weed Lab Archive

Manual Controls: Very small areas can be controlled by manual pulling, taking care to remove all parts and roots; several years of monitoring and repeated removal are needed as remaining seeds continue to sprout. Repeated mowing and/or prescribed burning will work on small areas but will not control large populations.
Chemical: Systemic herbicides such as glyphosate (Roundup), triclopyr (Garlon) and others used at the recommended rates can be effective. Mowing prior to application, to reduce plant mass, can increase herbicide effectiveness. Chemical control in early spring, prior to flowering and seed dispersal, will reduce but not eliminate need for follow-on monitoring and control. Repeat applications of herbicide during the initial year and in follow-on years generally are required, as seeds remain viable for several years.

Tom Heutte, USDA Forest Service

Alliaria Petiolata

Garlic Mustard

Native Origin: Europe and Asia. Brought to North America in the 1860s, garlic mustard had long been used by Europeans as a flavoring herb and for limited medicinal purposes. Also known as “Sauce-Alone” and “Jack-by-the-Hedge”, garlic mustard occurs throughout the eastern U.S. and Canada. Leaves and stems smell of garlic when crushed.

Chris Evans, River to River CWMA

Habitat & Ecological Impact: Thrives in moist shaded soils of floodplains, forests and roadsides. Disturbed areas are most susceptible to rapid invasion. Seeds may continue to ripen even on cut stems. Seeds are easily transported in muddy soils clinging to equipment tires, animal feet and hooves and humans’ shoes. Prolific seeds can persist in soils for up to 10 years. Plants produce root toxins that inhibit growth of other species. Once introduced to an area, garlic mustard monopolizes light, moisture, soil and space and quickly out-competes and eliminates native wildflowers, grasses and tree and shrub seedlings. Although deer do not eat garlic mustard, they may encourage plant growth by eating and removing native plants and by disturbing adjacent soils. While butterflies may nectar on the flowers, their larvae cannot eat the leaves.

Chris Evans, River to River CWMA

Description: A biennial herb, garlic mustard produces a low-growing rosette of green leaves in its first year and only flowers in the second year. Flowering plants are 2 to 3 ½ feet tall, with clusters of small white flowers produced in early spring. Like most plants in the mustard family, each flower has four petals arranged in the shape of a cross. The long, slender seedpods are produced in May. Once mature, the long brown pods persist through summer, holding shiny black seeds up to several thousand per plant.

Control & Management: Careful monitoring and repeat control is required over several years.
Manual: Light infestations can be hand-pulled, taking care to remove all roots. When flowers or seed stalks are present, all plant parts should be bagged and removed from the area.
Mechanical: If flowering stalks are cut at ground level, seed production will be reduced or even eliminated. All stalks should be bagged and removed from the area.
Chemical: Heavy infestations may be treated with foliar applications of systemic herbicide (Roundup). Great care should be taken to avoid non-target plants; repeat applications may be needed as long-lived seeds sprout.

James H. Miller, USDA Forest Service

Pueraria Lobata

Kudzu

Native Origin: The “Vine That Ate the South” had a lot of help getting established in the U.S. Originally introduced from China as an ornamental vine in 1876, its use as a fodder crop in Japan created more interest and, in the 1930s kudzu was widely promoted as the crop that would allow farmers to take up a life of leisure. Kudzu’s speedy growth, high-nitrogen-content stems and leaves and its drought tolerance were heavily promoted by the Soil Conservation Service, which paid farmers to plant the crop that “works while you sleep”. But the high hopes never panned out, for kudzu was difficult to bale as hay and easily damaged by grazing cattle. Even as farmers realized kudzu was no cure-all, the 73 million seedlings planted in the Southeastern U.S. from 1935 to 1941 responded to favorable growing conditions and absence of any predators. Kudzu simply grew and grew and grew.

Description: The vigorous perennial deciduous vine is a member of the pea family. Alternate leaves are compound with leaflets either palm-shaped or lobed into two or three portions. The pea-like flowers are one-half inch long and appear in long clusters. The very fragrant purplish flowers appear from summer through early autumn and are succeeded by flattened brown, hairy pods, each containing three to 10 seeds.

David J. Moorhead, Univ. of Georgia

Habitat & Ecological Impacts: Although initially not considered hardy outside of the deep south (USDA Zone 7), kudzu now occurs to central Illinois and northern New York. It grows well in most soils and under a wide range of conditions, but is especially vigorous along forest edges, roadsides, and disturbed areas in full sun. Kudzu replaces all other vegetation by smothering everything under a dense blanket of leaves. Kudzu can and does grow over buildings, power lines, trees, shrubs and open fields. The vines can grow up to 50 feet per year with stems that are one-half to 4 inches in diameter on vines that can extend up to 100 feet from the crown. The massive extend up to 100 feet from the crown. Massive taproots, up to seven inches in diameter and six or more feet in length, can weigh more than 400 pounds, and each root crown can produce up to 30 vines. Seed production varies greatly, with vines growing in full sun and climbing on sturdy structures able to produce up to 1800 seeds per square meter of soil surface. Kudzu also reproduces vegetatively by root runners, by rhizome, and by extension of vines that can root into the soil to produce new crowns.

James H. Miller, USDA Forest Service

Manual Controls: Repeatedly cutting or mowing the vines just above ground level can help reduce invasiveness and retard or prevent seed production.
Chemical: General use systemic herbicides, such as glyphosate (Roundup), triclopyr (Garlon), and others offer effective control. Vines should be sprayed as high as possible. Treatment and control measures may require a number of years due to extensive root development, suckering and continued seed viability.

James H. Miller, USDA Forest Service

Albizia julibrissin

Silk Tree, Mimosa

Native Origin: Eurasian in origin, found from Iran to Japan; also called Mimosa, Silky Acacia, and, rarely, Sensitive Tree, it was first imported into the U.S. in 1745 as an ornamental and remains popular with gardeners, due to its showy fragrant flowers, finely-cut foliage and ease of cultivation.

Description: A member of the Pea family, Silk Tree can grow 10 to 50 feet in height. Leaflets of the compound leaves will curl and close like pages in a book when handled. Numerous showy, powder-puff shaped flowers appear from June through August, and are followed by flat pods about six inches long that contain the large flat seeds. The seeds can persist for many years, and though the majority are dropped near the parent plant, seeds are eaten and passed on by animals and can be washed into streams and quickly disbursed to new areas.

David J. Moorhead, Univ. of Georgia

Habitat: Grows and flowers best in full sun, but will grow in a variety of conditions. Spreads quickly to form dense colonies in disturbed areas. Often found along roadsides and near areas where it has escaped from cultivation, it can become a serious pest along streams where seeds are easily spread. Can reproduce both by seed and vegetatively; top-killed trees quickly re-sprout and re-grow.

Ecological Impacts: The dense stands of wild-growing silk trees quickly out-compete native trees and shrubs and shade-out native wildflowers and grasses.

Control & Management: Repeat controls may be required due to long-lived seeds and to repeat suckering from cut stumps.

USDA Forest Service

Manual & Mechanical: Small seedling trees can be hand-pulled, taking care to remove the entire root system. Girdling of large trees can be effective: the girdle should be made about six inches above ground and should encircle the entire trunk in a deep cut that goes well within the bark. Treating the stump with herbicide will reduce re-sprouting; subsequent root sucker growths should be cut and treated with herbicide.
Chemical: Foliar treatment with systemic herbicide, such as Roundup, can be effective, but care should be taken to avoid non-target species. Herbicides, such as triclopyr, that act only on broad-leaf species may be preferred in locations with native or other desirable grasses. On sites near wetlands or streams, use of foliar herbicide treatment can adversely impact animal populations, and a combination of manual control, followed by minimal herbicide application to cut stumps may be best.

Leslie J. Mehrhoff, Univ. of Connecticut

Celastrus Orbiculatus

Oriental Bittersweet

Native Origin: Also called, Asiatic/Asian bittersweet, this species is native to Korea, China and Japan. This deciduous, woody perennial vine was introduced from Asia as an ornamental, prized for its showy red-orange mature seeds. It unfortunately bears very close resemblance to, and can even hybridize with, our native American bittersweet, Celastrus scandens. Also producing showy fruits, native American bittersweet populations have been greatly reduced due to over-collection of vines for use in dried flower and wreath arrangements.

James H. Miller, USDA Forest Service

Description: Oriental bittersweet vines are light brown in color, two to four inches in diameter and up to 60 feet in length. Leaves are two to five inches long and are nearly as wide as long, making them nearly round. The glossy, finely toothed leaves alternate along the stem. Small, green-white flowers in clusters appear from May through June all along the vine near the leaf stems. Mature fruits open to show three seeds each covered in red-orange papery seed coats. While the two species are very similar in both appearance and habitat, American bittersweet has leaves that are oval and much less rounded. American bittersweet flowers and fruits only at the ends of the vines, rather than all along the vine. Before beginning control measures, great care should be taken to correctly identify and distinguish between the two species.

Ecological Effects: Oriental bittersweet aggressively invades forests, open woodlands, and forest edges. It grows through and over other vegetation, shading out and smothering herbaceous plants and kills trees and shrubs by blanketing them with foliage and girdling trunks, even uprooting trees by its massive weight. Because Asiatic bittersweet produces an abundance of fruits along the vine lengths, it is a prolific seeder; the plants also reproduce vegetatively through root suckering. Because it hybridizes with American Bittersweet, it is replacing an increasingly rare native plant.

James H. Miller, USDA Forest Service

Manual Control: Plants can be pulled, taking care to remove as much root as possible. If fruits are on the vines, all parts should be removed from the area and destroyed to prevent new growth.
Chemical: Systemic herbicides, such as glyphosate (Roundup) or triclopyr (Garlon) are effective controls. Herbicide take-up can be maximized by application onto cut stems.

Chris Evans, River to River CWMA

Dipsacus fullonum & D. laciniatus

Common (Fuller’s) & Cut-leaved Teasel

Native Origin: Both species are native to Europe, North Africa and Asia. European settlers probably introduced common teasel early in the 18th century. “Fulling” cloth meant the process of cleaning, pulling, weighting, and compressing fibers into felt and other textiles; dried flower heads, attached to spindles, were used to raise nap on cloth.

Description: Mature teasel plants die after flowering and seed set. Seedlings form a basal rosette of leaves that grows at least one year, often for several seasons, as the long taproot up to two feet deep develops. When the plant has accumulated enough energy stores, the long stalk, tipped with distinctive flower heads, appears.

The oval to oblong leaves of the rosette can spread 2 feet or more. Flowering stalks can reach 6 to 7 feet; stem leaves are opposite and joined around the stem, forming cup-like reservoirs. Leaves of common teasel are long and toothed with prickles on the margins; cut-leaf teasel leaves are lobed and hairy on the margins. The small, individual flowers are densely packed along the oval heads, which bear long up-turned bracts at the base. Common teasel has purple to pinkish-white flowers; cut-leaved teasel flowers are white. Blooming time ranges from June through October.

Ohio State Archive

The rapid spread of teasel during the last 30 years may be due to the expansion of highway systems as mowing equipment readily carries seeds. Teasel also is grown as an ornamental and is a popular addition to dried-flower arrangements, a use that has aided seed distribution particularly around cemeteries.

Habitat & Ecological Effect: Teasel grows in open sunny areas in wet to dry conditions. One plant can produce more than 2,000 seeds; seed remains viable for at least two years and germination rates up to 80% can occur. Immature seed heads can continue to produce viable seed.While both species can invade natural areas, cut-leaved teasel is more aggressive and can quickly take over an area, creating a single species monoculture. Teasel out-competes and replaces native vegetation, and degrades native plant prairies, glades and meadows, and open woodlands.

Control: Individual plants can be dug and removed, taking care to get as much of the root as possible to reduce or prevent resprouting. Flowering stalks can be cut and removed but should not be cut until flowering has begun, since the plants retain enough energy reserves to send up new stalks. Flowering heads should be removed from the area and destroyed, since even immature flowers can produce seed.

Steve Dewey, Utah State Univ.

Chemical: Foliar application of systemic herbicide such as glyphosate (Roundup) can be used in areas of extensive teasel growth and can be applied to plants in the rosette stage during the fall, when most native plants have entered dormancy but teasel remains active. Repeat monitoring and control measures generally will have to be done.

Chris Evans, River to River CWMA

Euonymous Fortunei

Winter Creeper, Climbing Euonymous, Gaiety, Emerald Gaiety

Native Origin: Introduced from China as an ornamental plant in 1907, Euonymous fortunei and more than a dozen hybrids of the species, remains a popular ornamental vine and ground cover. More than a dozen cultivars have been created and were selected for foliage color, hardiness and growth form. Unfortunately, the very characteristics that make it a “good” garden plant, evergreen and continued photosynthesis in all seasons, ease and rapidity of growth in sun or shade, drought and moisture tolerance, make it a real threat to natural areas.

Description, Habitat & Ecological Impact: An evergreen vine, winter creeper can grow in shrub form, as dense ground-hugging mats, as vines climbing to 70 feet, or in all three forms. Oblong leaves usually are one to two inches long, with slightly toothed edges; all leaf surfaces look and feel somewhat leathery-to-waxy. Stems are greenish to green-gray, slightly warty and carry rootlets or aerial roots. Small green-white flowers are produced in summer, followed by reddish capsules, each containing seeds with their own orange coating. Winter creeper reproduces by seed and vegetatively. Lateral shoots spread from the main stems and new plants also may grow from rootlets produced all along the stems.

Keith Langdon, National Park Service

Tolerant of poor soil and drought, it grows well and reproduces in all light conditions from full sun to full shade. It out competes native plants by sapping nutrients and moisture and can blanket plants, preventing photosynthesis. Vines can grow up and topple trees and shrubs. Dense vegetative mats can completely replace native flowers, ferns, grasses, sedges, and tree seedlings in woodland and glade areas.

Manual Control: Grubbing out the vines can be effective for small areas and where herbicide use could damage non-target plants or harm wildlife. Pulling and digging when soil is moist aids in removal of all plant parts and roots. All pieces and seeds should be removed to prevent re-rooting. Even where feasible, mowing or cutting of ground-matted populations alone is not effective since remaining stems and roots will resume growth.

Chemical: Foliar application of herbicide can be used. Systemic herbicides, such as glyphosate (Roundup) or triclopyr (Garlon) should be used according to label instructions. Use of a surfactant (wetting agent) generally is needed due to the leathery, waxy leaf surfaces.

Herbicide applied to cut stems may be the best method in areas where foliar spraying would damage wildlife or desirable native plants.

Leslie Mehrhoff, Univ. of Connecticut

Humulus japonicus

Japanese Hop

Native origin: East Asia

This member of the Hemp plant family was brought to the U.S. from East Asia in the 1880s, and still is used to flavor Asiatic medicinal tonics and as an ornamental vine.

Description: This usually annual vine climbs by twining and does not have tendrils. The rough-textured, tooth-edged paired leaves are two to four inches long and have five to seven (sometimes nine) lobes. The stout stems and leaves carry numerous sharp, downward-pointing prickles that can irritate the skin and may cause dermatitis and blistering. The small greenish-yellow male flowers occur on separate plants from the larger light green, drooping cone-like structure that holds the female flowers. Round seeds are about one-eighth inch in diameter and turn light brown with dark specks as they mature.

Leslie Mehrhoff, Univ. of Connecticut

Habitat: Will grow in a variety of soil and light conditions but prefers moist soils and sunlight. Most commonly found near stream banks and in floodplains, Japanese Hop readily invades open woodlands and forest edges. It is hardy to USDA zone 5 and plants may survive mild winters. New infestations occur as seeds are readily spread by animals, machinery and floodwaters.

Ecological Threat: With a 10-foot annual growth rate Japanese Hop vines can quickly overgrow low vegetation, shrubs and small trees. Dense mats several feet in depth block light to all other plants and can leave bare ground which then serves as an even better seedling growth area in following years. Several thousand plants per acre can occur in heavily infested areas.

Manual Control: The shallowly rooted plants can be pulled from moist soil, taking care to get the entire root mass. This method is effective in spring before the plants set seed. It is important to avoid skin contact with the plant as blistering and dermatitis may result from the prickles on the stems and leaves.

Mechanical Control: Repeat and frequent mowing, where possible, may control this plant, particularly in areas where winter kills the vines. Mowing must be repeated to prevent seed set.

Chemical: Foliar spraying with general use systemic herbicides, such as glyphosate (Roundup) is effective. Repeat treatments may be needed to penetrate the dense vine coverage and/or to control new seedlings. Manufacturers’ directions should be followed, particularly when control measures are to be done near water.

James H. Miller, USDA Forest Service

Lespedeza cuneata sericea lespedeza

Chinese lespedeza, Chinese bush clover, silky bush clover, hairy lespedeza/bush cloverLonicera japonica

Native Origin: Native to Asia, silky bush clover was introduced in the 1940s as a forage and hay crop for livestock, particularly on poor, eroded soils. Another introduction done for good purposes, this species didn’t live up to expectations for it contains high levels of tanins, making it unpalatable to livestock, and doesn’t work well as an erosion control agent. It should not be confused with our native lespedezas (bush clovers) that occur naturally in prairies, glades and open woodlands.

Dan Tenaglia, MissouriPlants.com

Description, Habitat & Ecological Effect: This member of the Pea family, is a perennial herbaceous plant that grows 3 to 5 feet tall. Compound alternate leaves have three leaflets, each one-half to one inch long, that are narrow and pointed at the end. Somewhat woody leaves and stems both carry small flattened hairs and have a silver gray-green color. Small cream-white flowers bloom from late July into October. Each flower produces one small shiny, flattened oval seed that may range in color from tan through purple brown. Reproduction is almost entirely by seed. Seeds are disbursed to new areas by animals. Seeds can remain viable for up to 20 years, and, in some conditions, for far longer. The thick seed coat needs some form of scarification before germination can occur; this can be done by the acid encountered in an animal’s digestive tract , by any force that rubs, rasps and removes the husk, or by a slower process of simple repeat weathering. Chinese bush clover is tolerant of a wide variety of soil types, and will grow on eroded and sterile soils; the plants grow woody taproots, up to 4 feet deep, that enable a high degree of drought tolerance. It will tolerate and reproduce in light shade. It grows well in open areas and has invaded and replaced native vegetation in open woodlands, savannahs, prairies, glades, fence rows, borders of wetlands and ponds, and roadsides (where even further spread occurs by mowing equipment spreading seed). Once established, it out competes native plants for soil nutrients and moisture and even sunlight. Long seed viability guarantees years of continued new growth.

James H. Miller, USDA Forest Service

Manual: Only the newest, youngest, least-well established plants can be hand-pulled as the taproot makes this method impracticable. Mowing the plants in flower bud stage for several years can prevent seed production and slowly sap the plant’s energy stores. Burning at any time of the year will scarify seed in the soil and generally results in more seedling plants.
Chemical: Systemic herbicides, such as glyphosate (Roundup) and triclopyr (Garlon) and others offer effective control measures, particularly when used in early to mid-summer, before new seeds mature. Repeat applications may be needed.

James H. Miller, USDA Forest Service

Elaeagnus umbellata Autumn Olive

Common Names: autumn olive, oleaster, Japanese or Asiatic Silverberry

Native Origin: This East Asian native was introduced to the U.S. in the 1830s as an ornamental plant and for erosion control. It now occurs throughout the Eastern and Midwestern U.S. and is moving into the Central Plains and West.

Description: A deciduous shrub or small tree that grows to about 20 feet tall. Leaves are dark green with silver-white scales on the underside. The alternate, oval to lance-shaped leaves are untoothed. Small light yellow flowers appear along the twigs early in spring and are followed by great quantities of small, red, juicy fruits. Birds forage on the berry-like fruits, contributing to the spread of this plant.

James H. Miller, USDA Forest Service

Habitat: Autumn olive grows well in a variety of soil types, including sandy, loamy and even clay textured soils. Its roots fix nitrogen, which allows it to flourish even in poor soils. Mature trees tolerate some shade, but produce more fruit in full sun. It is drought tolerate and invades grasslands, glades, sparse woodlands, pastures, fields and roadsides.

Ecological Impacts: Rapid growth and prolific seeding makes Autumn olive a serious invasive plant pest. Plants rapidly establish large and growing colonies. The nitrogen fixing ability can adversely impact native plants that depend on infertile soils.

Pennsylvania Department of Conservation and Natural Resources - Forestry Archives

Similar species: Autumn olive may be confused with Russian olive, a closely related species, which also is a nonnative invasive. Russian olive is usually very thorny (Autumn olive is sparsely thorned), and has larger, olive-shaped, mealy fruits.

Control and Management: Because the stumps sprout readily and seeds are so abundant, resprouts and new seedlings are common. Autumn olive may require repeat treatment for full control.

Manual: Seedlings and sprouts can be hand-pulled from moist soil to ensure removal of the entire plant and roots. Please note: on larger plants, cutting alone results in thicker, denser growth, as does burning during the dormant season.

Chris Evans, University of Georgia U. S.

Chemical: Foliar spraying with systemic herbicide is effective. Since spraying must be done when plants are actively growing, care should be taken to avoid non-target species as much as possible.

Combination: On sites, such as near wetlands or streams, where largescale spraying is not desirable or when impact to non-target species is to be minimized, a combination of manual and chemical means may be best. In these circumstances, cut the shrubs to the lowest possible common stem(s) and then carefully paint, daub or squirt systemic herbicide on the remaining cut surface. This is most effective when fruits have not formed or are not ripe; otherwise, care must be taken to remove the plant(s) from the area to avoid scattering seed.