1. Lonicera L. (honeysuckle)
Plants shrubs or
lianas. First-year twigs 1–2 mm thick, the pith solid or hollow. Winter
buds more or less ovoid to conical, with 2 to several overlapping scales. Leaves
sessile or with short, unwinged petioles, the uppermost leaves sometimes
strongly perfoliate (fused at the base to form a single blade surrounding the
stem). Stipules absent. Leaf blades simple, unlobed or in L. japonica
the first leaves of the season sometimes irregularly lobed, elliptic to ovate,
oblong, or oblanceolate, the margins entire. Flowers in pairs in the leaf
axils, or in 1–4 whorls terminal on the branches, or in L.
purpurea in 1 or 2 sessile pairs from buds on second-year
branches, the individual flowers usually subtended by small, paired bractlets,
the inflorescences subtended by bracts. Corollas 13–48 mm long,
actinomorphic and narrowly tubular-funnelform or zygomorphic with spreading to
recurved lobes, sometimes the lobes similar in size and sometimes shape but
positioned zygomorphically, white, pink, yellow, orange, or red. Style
8–50 mm long. Fruits berries, more or less spherical (oblong-ellipsoid
in L. purpusii), red, black, or rarely yellow at
maturity. Seeds few, 2.5–6.0 mm long, oblong-ovate to oblong-elliptic
in outline, sometimes irregularly so, often somewhat flattened, one or both
sides sometimes slightly angled or with a pair of shallow longitudinal grooves,
the surface smooth or more commonly with a minute network of low ridges,
reddish brown to dark brown. About 180 species, North America, Europe, Asia.
have long been very popular in horticulture, and numerous species and cultivars
exist in cultivation. The plants are easy to grow, tolerant of difficult
conditions, and their flowers are attractive and (in many species) fragrant.
The berries attract birds in the autumn. However, some exotic species of Lonicera
are very invasive in natural plant communities, and the genus includes two of
the worst invasive exotics in Missouri, L. japonica and L. maackii.
In Missouri, two
escaped taxa of shrubby honeysuckles exist that arose through past
interspecific hybridization, but whose parents do not occur in the state.
Because these fertile hybrids are not easily related to any of the other
species in the state, they are accorded full treatments below.