Lonicera maackii (Rupr.) Maxim.

Amur Honeysuckle, Bush Honeysuckle

© DETenaglia

Family - Caprifoliaceae

Habit - Shrub to 5.0 m tall, the main stems erect or ascending, self-supporting.

Stems - Woody, multiple from base. Young twigs moderately to densely pubescent with short, curved, sometimes more or less tangled, unbranched hairs, the pith hollow. Older stems usually tan with faint longitudinal striping visible. Winter buds ovoid, hairy.

	Stem and node.
© SRTurner

	Older stem. The light color with darker striping is characteristic of this species.
© SRTurner

	Hollow pith.
© SRTurner

Leaves - Opposite, petiolate, simple. Petioles to 6 mm long, tomentose. Blades 3.5-9.5 cm long, 1.5-4.0 cm wide, elliptic to ovate-elliptic, angled or rounded to more commonly tapered at the base, tapered to a sharply pointed tip, the margins entire, the upper surface nearly glabrous, the lower surface and margins moderately pubescent with fine, mostly curved hairs, light green to pale green, not glaucous.

	Leaves.
© SRTurner

	Leaves adaxial.
© SRTurner

	Leaf abaxial.
© SRTurner

	Leaf abaxial surface.
© SRTurner

	Pressed leaves.
© DETenaglia

Inflorescence - Flowers paired in the axils of the leaves on current year's growth (first-year wood), each pair at the tip of a stalk 2-5 mm long (often appearing sessile at fruiting), the 2 bracts each 1-4 mm long, free, linear, hairy, the pair of bractlets on opposite sides of each flower 1/2 as long to about as long as the ovary, free, oblong-obovate to nearly circular.

	Inflorescences.
© SRTurner

	Inflorescences.
© SRTurner

Flowers - Calyces with stalked glands and long, straight hairs, the lobes 0.2-0.5 mm long, triangular. Corollas 15-25 mm long, strongly zygomorphic, divided about 1/2 of the way to the base into 5 more or less spreading lobes of about equal length, the upper lip shallowly 4-lobed, the lower lip 1-lobed, the tube not or very slightly swollen or pouched on the lower side near the base, white, turning yellow after pollination or with age. Stamens (5) and style exserted from the corolla, shorter than the corolla lobes, the style hairy. Filaments to 1.1 cm long, pubescent at base, glabrous near apex, white. Anthers yellow, to 6 mm long, 1.2 mm broad. Ovary free, inferior, with 2-5 locules, the placentation axile. Style 1 per flower, the stigma capitate. Ovules 1 to numerous per locule.

	Calyces and bracts.
© SRTurner

	Flowers.
© DETenaglia

	Flowers.
© SRTurner

	Flowers.
© SRTurner

	Flowers, rear view.
© SRTurner

Fruits - Berries 4-7 mm in diameter, orangish red to red.

	Fruits.
© SRTurner

Flowering - April - June.

Habitat - Forests, bases and ledges of bluffs, streambanks, fencerows, gardens, railroads, roadsides, and shaded, disturbed areas.

Origin - Native to Asia.

Lookalikes - Flowers are similar to those of several other members of the genus. This is the only common shrubby honeysuckle in Missouri. Vegetatively the plant can resemble native species such as wahoo (Euonymus atropurpureus).

Other info. - This plant is probably the most noxious invasive shrub which plagues most parts of Missouri. It is found across the state, though is very under-collected because field botanists detest it and want nothing to do with it. When flowering it is easily identified through its shrubby habit and distinctive flowers, which are pure white when fresh but turn yellow with age. Identification in the vegetative state is not hard but requires a little more practice and study, which the images above are intended to facilitate. In particular, note the leaf shape and their opposite arrangement, lack of teeth on the leaf margins, the pale striping which is almost always present on older, woody stems, and the hollow pith.

This nasty and aggressive species was brought to North America in 1855 as an ornamental, and further "improved" by USDA Soil Conservation Service. Until the mid-1980s it was widely planted for erosion control and as ornamental hedges. Since then its aggressive nature has been widely recognized, and countless hours of volunteer labor have expended in attempts to control its invasion of natural areas. Large expanses of woodland, particularly near urban centers, can be overrun with this pest to the extent that little else grows. Large specimens can reach 20' in height with stems the diameter of man's arm. The plant is one of the first to leaf out in the spring, and one of the last to lose leaves in the fall, so it effectively robs light from anything below its level. Efforts at control and eradication are useful but are a never-ending task. Also, anyone wishing to aid in eradication efforts should be thoroughly competent in the plant's identification, since damage can be done by inadvertent removal of beneficial native species. Because of the hollow pith, smaller stems can be snapped off effectively, but although this will temporarily slow the growth of the bush, it will not kill it. The most effective control appears to be cutting the stems near ground level and applying a concentrated herbicide.

Deliberate planting of this species would be appallingly irresponsible.

Photographs taken off the MKT Trail in Columbia, MO., 5-12-04 (DETenaglia); also at Weldon Spring Conservation Area, St. Charles County, MO, 9-26-2008, and Shaw Nature Reserve, Franklin County, MO, 5-17-2022 (SRTurner).