Japanese Honeysuckle (Lonicera japonica)
Miller, J.H., E.B, Chambliss, N.J. Loewenstein. 2010. A Field Guide for the Identification of Invasive Plants in Southern Forests. General Technical Report SRS-119. Asheville, NC. United States Department of Agriculture, Forest Service. 126 p.
Semi-evergreen to evergreen woody vine, high climbing and trailing to 80 feet (24 m) long, branching and often forming spotty to extensive arbors in lower and upper forest canopies and/or ground cover under canopies and in new forests, rooting at nodes along leaf-covered vines (stolons).
Slender woody vine becoming stout to 2 inches (5 cm) in diameter, with crosssection round and opposite branching. Brown and hairy becoming tan barked, fissured, and sloughing with age. Rooting at low nodes.
Opposite, broadly ovate to elliptic to oblong, base rounded, tips blunt pointed to round. Length 1.6 to 2.6 inches (4 to 6.5 cm) and width 0.8 to 1.5 inches (2 to 4 cm). Margins entire but often lobed in early spring. Both surfaces smooth to rough hairy, with undersurface appearing whitish.
April to August. Axillary pairs, each 0.8 to 1.2 inches (2 to 3 cm) long, on a bracted stalk. White (or pink) and pale yellow. Fragrant. Thin tubular, flaring into 5 lobes in 2 lips (upper lip 4 lobed and lower lip single lobed), with the longest lobes roughly equal to the tube. Five stamens and 1 pistil, all projecting outward and becoming curved. Persistent sepals.
Fruit and seeds
June to March. Nearly spherical, green ripening to black, glossy berry 0.2 inch (5 to 6 mm) on stalks 0.4 to 1.2 inches (1 to 3 cm) long. Two to 3 seeds.
Most commonly occurring invasive plant in the South, overwhelming and replacing native flora in all forest types over a wide range of sites or occurring as scattered plants. Often coexisting with other invasive plants. Occurs as dense infestations along forest margins and right-of-ways as well as under dense canopies and as arbors high in canopies. Shade tolerant. Persists by large woody rootstocks and spreads mainly by rooting at vine nodes and less by animal-dispersed seeds. Infrequently seeding within forest stands with very low germination. Seed survival in the soil is less than 2 years.
Resembles yellow jessamine [Gelsemium sempervirens (L.) W.T. Aiton], which has narrower leaves and hairless stems. Also resembles native honeysuckles (Lonicera spp.) that usually have reddish hairless stems and hairless leaves and do not form extensive infestations.
History and use
Introduced from Japan through England in the early 1800s. Traditional ornamental, valued as deer browse, with some value for erosion control. Still planted in wildlife food plots to encroach on adjacent lands.
The most pervasive invasive plant throughout the region with the most frequent and dense infestations in east-central AL and a sizeable number in central MS and TN, as well as northwest SC.
- Do not plant. Remove prior plantings, and control sprouts and seedlings. Bag and dispose of plants and fruit in a dumpster or burn.
- Treat when new plants are young to prevent seed formation.
- Pull, cut, and treat when fruit are not present.
- Manually pull when soil is moist to ensure removal of all stolons and roots.
- Prescribed burning in spring will reduce dense ground mats and sever climbing vines for more effective herbicide treatments to resprouting vines. However, resprouting after one prescribed burn can intensify infestations. Climbing honeysuckle vines can become ladder fuels for fire to reach tree canopies. Repeated burning treatments will not control the plant, and burning is difficult due to absence of fine fuels under honeysuckle mats.
- Readily eaten by goats.
Recommended control procedures
- When nontarget damage is not a concern, apply Escort XP* with a surfactant to foliage (June to August) either by broadcast spraying 2 ounces per acre in water (0.6 dry ounce per 3-gallon mix) or by spot spraying 2 to 4 ounces per acre in water (0.6 to 1.2 dry ounces per 3-gallon mix).
- Or treat foliage with one of the following herbicides in water with a surfactant (July to October, or during warm days in winter), keeping spray away from desirable plants: a glyphosate herbicide as a 2-percent solution (8 ounces per 3-gallon mix) or Garlon 3A or Garlon 4 as a 3- to 5-percent solution (12 to 20 ounces per 3-gallon mix).
- Or cut large vines just above the soil surface and immediately treat the freshly cut stem with a glyphosate herbicide or Garlon 3A as a 20-percent solution (5 pints per 3-gallon sprayer) in water with a surfactant (July to October). ORTHO Brush-B-Gon, Enforcer Brush Killer, and Vine-X are effective for treating cut-stumps and readily available in retail garden stores (safe to surrounding plants) while Brush-B-Gon and Enforcer Brush Killer can be mixed in water and used as foliar sprays.
* Nontarget plants may be killed or injured by root uptake.