Reynutria japonica ( Latin Reynoútria japónica ) is a dioecious perennial herbaceous plant , a species of the genus Reinutria of the buckwheat family ( Polygonaceae ).
| Japanese Reinutria |
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| Scientific classification |
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| Order : | Caryophyllanae Takht. , 1967 |
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| International scientific name |
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Reynoutria japonica houtt. , 1777 |
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An invasive species originating from the Far East and brought into many regions of the world. Included in the list of the most dangerous invasive species according to IUCN . A hybrid with Sakhalin Reynoutria ( Reynoutria sachalinensis ) called Reynoutria Bohemica ( Reynoutria × bohemica ) is also a dangerous invasive species, in many regions it is even more common than the parent species.
Botanical illustration by A. Barnard of
Curtis's Botanical Magazine (1880)
Naked perennial herb with numerous hollow erect stems up to 3 m tall, rarely branched in the upper part, longitudinally lined, often with reddish-purple spots. The rhizome is thickened, strongly branched, woody, with ring-shaped structures that are scaly leaves, in old clones diverging by 5-7 m, with yellow-orange flesh.
The leaves on both sides are devoid of any pubescence, 5-12 × 4-9 cm, slightly leathery, ovate to wide elliptic in outline, whole-edged, pointed at the end, with a wide-wedge-shaped, truncated or rounded base. Petiole 1-2 cm long, with papillae, emanates from the stem-wide bell .
Stamen flowers with 8 stamens protruding from a whitish or greenish five-lobed perianth. Outer tepals of pistil flowers are keeled, winged when fruiting, not falling, wrapping around a three-rib achene. The fruit is 2-4 mm long, about 2 mm wide, brilliantly black or dark brown, on average 1.6 mg .
Homeland plants - Japan , China and Korea . It was allegedly brought to Europe in 1849, when it was grown by Philippe Siebold . In 1854, it was first planted in Great Britain; by the 1880s it had fled from culture. Around the same time, appeared in gardens in the United States. At the beginning of the 20th century, it began to actively spread throughout Europe.
Over a significant part of the secondary range, it propagates exclusively vegetatively, since, in particular, only female plants with sterile stamen flowers were brought to North America and Great Britain, while in the conditions of Central Russia, the seeds of a late-flowering plant do not ripen.
