Bill Johnson

Amur Honeysuckle

Lonicera maackii (Rupr.) Herder
Honeysuckle family (Caprifoliaceae)

Origin: China, Japan, Korea, and Russian Far East

Background
Amur honeysuckle was imported as ornamental into New York in 1898 through the New York Botanical Garden. It has been widely planted for wildlife cover and soil erosion control but long ago escaped from plantings and began reproducing on its own and spreading into natural areas. Other invasive exotic shrub honeysuckles include fragrant (L. fragrantissima), Standish’s (L. standishii), Morrow’s (L. morrowii), Tartarian (L. tatarica), and Bell’s (L. x bella), a hybrid between Tartarian and Morrow’s. These are less common in our area.

Distribution and Habitat
Amur honeysuckle is one of the most common and invasive bush honeysuckles found in the mid-Atlantic region. It occurs in most states in the eastern U.S. except for Minnesota, Maine and Florida and has been reported to be invasive in many. It is adaptable to a range of conditions from sun to deep shade and wet to dry. It occurs in disturbed habitats including forest edges, forest interiors, floodplains, old fields, pastures, and roadsides. Disturbance increases the likelihood of invasion. Amur honeysuckle grows especially well on calcareous soils.

Ecological Threat
Amur honeysuckle impedes reforestation of cut or disturbed areas and prevents reestablishment of native plants. It leafs out earlier than most natives and form dense thickets too shady for most native species. Additionally, researchers in the Midwest found increased nest predation of robins using Amur honeysuckle as a result of plant structure which facilitates access to nests by predators such as snakes. While the carbohydrate-rich fruits of exotic honeysuckles provide some nutrition for birds and rodents in winter, they do not compare to the lipid-rich fruits of native species that provide greater energy to sustain migrating birds.

Description and Biology

• Plant: upright, deciduous shrub up to 15-20 ft. high; pith of mature stems is hollow and white or tan (in contrast to solid white pith of native shrub honeysuckle species).
• Leaves: opposite, ovate with a tapered tip, lightly pubescent, and up to 3½ in. long.
• Flowers, fruits and seeds: flowers paired, tubular, white to pinkish, fading to yellow, less than 1 in. long, borne from leaf axils, five petals, upper 4 fused; fruits are red to orange-red berries produced in late summer and persist through the winter.
• Spreads: by fruits which are abundant and highly attractive to birds that consume them and defecate the seeds in new locations. Vegetative sprouting aids in the local spread and persistence. 
• Look-alikes: other exotic bush honeysuckles including Tartarian (L. tatarica) and Standish’s honeysuckle (L. standishii); native species of Lonicera like American fly honeysuckle (L. canadensis), swamp fly-honeysuckle (L. oblongifolia) and mountain fly honeysuckle (L. villosa); northern bush-honeysuckle (Diervilla lonicera) which has leaves with toothed margins.

Prevention and Control
Young plants can be pulled by hand, larger plants either pulled using weed wrench-type tool or cut repeatedly. Systemic herbicides containing glyphosate or triclopyr can be applied to foliage, bark or cut stems (see Control Options).