Contact: Kate K. Traut, Straughan Environmental | 301-362-9200 ext.117 | ktraut@straughanenvironmental.com
ANNAPOLIS, MD (June 7, 2010) – Chocolate vine, or fiveleaf akebia (Akebia quinata), may be a sweet-smelling delight in the garden, but it is quickly becoming one of Maryland’s most wanted invasive species. Its delicately trailing vines, exotic-looking palmate leaves, and chocolate-scented flowers are some of the reasons why gardeners eagerly use it in landscaping. With many folks itching to add new and exciting plants to their gardens, it is important to add Chocolate vine to your list of what to avoid at the nursery. Chocolate vine may begin in the garden as a pleasing ground cover or trailing/climbing vine, but its ability to grow up to 40 feet in one growing season is a testament to its invasive nature. Once it escapes beyond the garden, it poses a serious ecological threat to natural areas. Chocolate vine has been identified as an invasive species in Maryland and the surrounding Mid-Atlantic states; therefore, the Maryland Invasive Species Council has chosen chocolate vine as the June 2010 Invader of the Month.
This perennial, semi-evergreen woody vine forms trailing groundcover and twines up shrubs and trees. Its alternate leaves are divided into five stemmed leaflets (hence the name fiveleaf akebia), each notched at the tip. The smooth, dull-green leaflets are palmately arranged (joined at one point), and about 1.5-3 inches long. The stems are slender and brown and can create a curtain-like effect of many vines hanging from tree limbs. As mentioned, the small reddish flowers (some whitish varieties) are thought to have a chocolatey aroma. The vine blooms March-April. The flowers often do not produce fruit, but when they do, the fruit is an edible pod 2.5-4 inches long that ripens September-October. Chocolate vine is the best known species in its taxonomic family (Ladizabalaceae)
Chocolate vine is a native to Asia, specifically China, Japan, and Korea, and like many of its invasive and exotic brethren, it has adapted quite well to mid-Atlantic climes. It has escaped cultivation in 16 states and has been recognized as invasive in Kentucky, Virginia, District of Columbia, Pennsylvania, and New Jersey, as well as Maryland. Due to its shade- and drought-tolerance, it can invade an array of habitats but prefers full to partial sun areas with well-drained soils.
Chocolate vine was brought over from Asia as an ornamental species in the mid-1800s. It primarily spreads vegetatively, though birds can disperse seeds when fruits are produced. Long distance dispersal continues to occur primarily through the horticultural trade and other human activities. Once chocolate vine escapes into a natural area and becomes established, it overtakes native ground cover species and climbs into the shrub and tree layers, eventually out-competing those species for sunlight. Chocolate vine’s ability to turn a diverse native plant community into a dense monoculture has been documented in Maryland and is illustrated in the accompanying photo. When chocolate vine dominates a natural area, not only does it reduce plant diversity, but it also provides little benefit to animal species, thus reducing wildlife diversity.
How do we get this invasive species out of our natural areas and gardens? Prevention is always a key part of the equation, so do not plant chocolate vine or promote the use of it as an ornamental species. Instead, consider using Trumpet honeysuckle (Lonicera sempervirons) or Dutchman’s pipe (Aristolochia durior), two lovely native vines. Eradication is also a critical component of reducing the spread of chocolate vine. Methods to remove the species are dependent on the site and degree of infestation. Manual, mechanical, and chemical means of removal can each be effective, though combining methods may yield the best results. For example, cutting vines trailing into shrubs and trees combined with pulling up, chemically treating, and/or mulching ground cover (if a small infestation) may do the trick. For more information regarding the chocolate vine management and eradication, visit http://www.nps.gov/plants/alien/fact/akqu1.htm.
For more information, see:
South China Botanical Garden Checklist
For more information about Invasive Species of Concern in Maryland, visit www.mdinvasives.org
photos available electronically on request.