Appearance
Lonicera maackii is a woody perennial shrub that can grow up to 16.5 ft. (5 m) in height.

Foliage
The oppositely arranged leaves are ovate to lance-ovate in shape and measure 1.3-3.3 in. (3.5-8.5 cm) long. The tips of the leaves are acuminate. The leaves are dark green above and lighter on the lower surface. The veins of the leaves are pubescent.

Flowers
The white flowers are found in erect pairs that are on peduncles shorter than the petioles. The flowers measure 0.6-0.75 in. (1.5-2 cm) long and are bilabiate. The flowers appear on the plant from late May to early June, which is later than the other honeysuckles.

Fruit
The fruit are dark red in color, spherical in shape, and measure 0.25 in. (6 mm) in diameter. The fruit becomes ripe on the plant in the late fall.

Ecological Threat

Lonicera maackii can form large stands that prevent native shrubs and herbaceous understory plants from growing. The fruits persist on the branches into the winter when birds feed on them. In the spring, Lonicera maackii is one of the first plants to leaf out, giving it a competitive advantage. This shrub can bear fruit when it is as young as 3 to 5 years old. Though Lonicera maackii has not yet become a major problem in New England, it is very troublesome in the southern and midwestern parts of the country.

Resources

• A Field Guide for the Identification of Invasive Plants in Southern Forests - USDA Forest Service
• Southeast Exotic Pest Plant Council Invasive Plant Manual - SE-EPPC
• Element Stewardship Abstract - The Nature Conservancy
• Weeds Gone Wild: Alien Plant Invaders of Natural Areas - Plant Conservation Alliance
• Weed of the Week - USDA Forest Service
• Weed of the Week - USDA Forest Service
• Plant Invaders of Mid-Atlantic Natural Areas - National Park Service and U.S. Fish and Wildlife Service

Selected Images

Maps

Invasive Listing Sources

• Alabama Invasive Plant Council
• City of Ann Arbor Michigan Parks and Recreation
• Commonwealth of Pennsylvania, Department of Conservation and Natural Resources, 1994.
• Connecticut Invasive Plant List
• Connecticut Invasive Plant Working Group
• Delaware Invasive Species Council
• Delaware Invasive Species Council Invasive Species List
• Georgia Exotic Pest Plant Council - Category 2
• Hoffman, R. & K. Kearns, Eds. 1997. Wisconsin manual of control recommendations for ecologically invasive plants. Wisconsin Dept. Natural Resources, Bureau of Endangered Resources. Madison, Wisconsin. 102pp.
• Illinois Exotic Weed Act
• Indiana Invasive Species Council - Invasive Plant List
• Indiana Terrestrial Plant Rule
• Invasive Plant Association of Wisconsin
• Invasive Plant Species of West Virginia
• Jil M. Swearingen, Survey of invasive plants occurring on National Park Service lands, 2000-2007
• Jil Swearingen, personal communication, 2009-2017
• John Randall, The Nature Conservancy, Survey of TNC Preserves, 1995.
• Kentucky Exotic Pest Plant Council - Severe Threat
• Maine Invasive Plants
• Maryland Code and Regulations of Invasive Plants
• Maryland Cooperative Extension Service.  2003. Invasive Plant Control in Maryland. Home and Garden Information Center, Home and Garden Mimeo HG88. 4 pp.
• Maryland Department of Natural Resources Policy: Restriction on Planting Exotic Invasive Plants
• Maryland Invasive Species Council - Invasive Species of Concern in Maryland
• Massachusetts Invasive Plants Advisory Group List
• Massachusetts Noxious Weeds
• Massachusetts Prohibited Plant List
• Minnesota Noxious Weeds
• National Park Service, Mid-Atlantic Exotic Plant Management Team Invasive Plant List
• National Park Service, National Capital Region Exotic Plant Management Team Invasive Plant List
• New Hampshire Invasive Species Committee. 2005. Guide to Invasive Upland Plant Species in New Hampshire. New Hampshire Department of Agriculture,  Markets and Food Plant Industry Division and New Hampshire Invasive Species Committee.
• New Hampshire Prohibited Invasive Species
• New Jersey Invasive Species Management Act
• New Jersey Invasive Species Strike Team 2017 Invasive Species List
• New York Regulated and Prohibited Invasive Species - Prohibited
• Non-Native Invasive Plants of Arlington County, Virginia
• Non-Native Invasive Plants of the City of Alexandria, Virginia
• Nonnative Invasive Species in Southern Forest and Grassland Ecosystems
• Ohio Invasive Species Council
• Ontario’s Invading Species Awareness Program Tracked Species List
• Pennsylvania Department of Conservation and Natural Resources Invasive Plants
• Pennsylvania Noxious Weeds
• Plant Invaders of Mid-Atlantic Natural Areas
• Reichard, Sarah. 1994.  Assessing the potential of invasiveness in woody plants introduced in North America. University of Washington Ph.D. dissertation.
• Rhode Island Natural History Survey
• South Carolina Invasive Pest Council
• Tennessee Exotic Pest Plant Council
• Tennessee Noxious Weeds
• Vermont Noxious Weeds
• Virginia Invasive Plant Species List
• WeedUS - Database of Plants Invading Natural Areas in the United States
• West Virginia Invasive Species Strategic Plan and Volunteer Guidelines 2014
• West Virginia Native Plant Society, Flora West Virginia Project, and West Virginia Curatorial Database System, September 3, 1999
• Wisconsin's Invasive species rule – NR 40

References