A favorite of bees, butterflies and hummingbirds, Japanese honeysuckle is a semi-evergreen vine that keeps its leaves in temperate climates late into the winter. The white or yellow tubular flowers of Lonicera japonica form in pairs at the leaf axils and the two to three-seeded fruits are small, black, and enjoyed by songbirds such as cedar waxwings.

Japanese honeysuckle was introduced in North America, and as an exotic, is often considered an invasive pest or weed species. It is infamous for its climbing, strangling, and shading growth patterns that can alter or destroy native understory and herbaceous layers in the prairies, sand barrens, glades, flatwoods, savannas, floodplain, and upland forests that it invades. Because the plant spreads by vegetative stems, grazing or mowing is not as effective as are prescribed burns and herbicides, such as the glyphosphates (trade name Roundup) and 2,4-D (Crossbow). In fire-adapted communities, periodic spring burning seems to control this invasive vine without chemical application. In its native habitat in Japan and other parts of Southeast Asia, the plant has natural enemies including a honeysuckle aphid.

Japanese honeysuckle differs from the three species of native honeysuckle in the United States, which are also in the family Caprifoliaceae, by leaf pattern and attachment. L. japonica features opposite leaves that are not united and that form near the tips of the vines while the leaves of the native species are united at the base and form a single leaf surrounding the stem. Introduced to the United States in 1806 at Long Island, New York as a groundcover by horticulturists, and for controlling erosion by soil scientists, the plant did not completely spread throughout the United States until the early 1900s. The northern range of this Asiatic honeysuckle is limited by cold winters, and it appears to spread to new areas via seeds dispersed by birds. The semi-evergreen nature allows the invasive vine to gain an advantage over the native vegetation it climbs over by growing before and after the host plant's growing season. Other species of exotic honeysuckle have become established, or invasive, in the United States after introduction as bush honeysuckles and being spread by avian seed dispersal.

Children love picking the delicate white and yellow flowers, attracted as the pollinators are, by their intense sweet aroma, and after peeling away the flower parts, enjoy the golden nectar for a sweet, but tiny treat. In China, L. japonica is a valued medicinal herb that contains anti-complementary polysaccharides and polyphenolic compounds that inhibit human platelet activation. A mixture of honeysuckle flower buds plus parts of other plants known as "Aden I" is reported to feature antibiotic and antiviral powers. Herbalists use the flowers and leaves as a treatment for chicken pox and some Korean poultry producers use the exotic as a feed additive to increase productivity of broiler chickens. Whether we love it or loathe it, the sweet-smelling weed is here to stay.

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