Bohemian knotweed is a

nothospecies #REDIRECT Hybrid name In botanical nomenclature, a hybrid may be given a hybrid name, which is a special kind of botanical name, but there is no requirement that a hybrid name should be created for plants that are believed to be of hybrid origin. ...

that is a cross between

Japanese knotweed ''Reynoutria japonica'', synonyms ''Fallopia japonica'' and ''Polygonum cuspidatum'', is a species of herbaceous perennial plant in the knotweed and buckwheat family Polygonaceae. Common names include Japanese knotweed and Asian knotweed. It is ...

and

giant knotweed ''Reynoutria sachalinensis'' (giant knotweed or Sakhalin knotweed Japanese オオイタドリ ''ooitadori'', Russian Горец сахалинский, Гречиха сахалинская; syns. ''Polygonum sachalinense'', ''Fallopia sachalinen ...

. It has been documented as occurring in the wild in Japan. The scientific name is accepted to be ''Reynoutria'' × ''bohemica'', but it may also be referred to as ''Fallopia'' × ''bohemica'' and ''Polygonum'' × ''bohemicum''. The species was first described by and in the

Czech Republic The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The ...

in 1983.

Description

The species is an herbaceous perennial that can spread through seeds and

rhizome In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...

s. It can exceed 3.5 meters in height. Leaves are larger than those of Japanese knotweed, and leaf bases are less squared. White flowers typically open in August. The species can be verified by the hairs along the mid-vein on the undersides of leaves, which are of different shape and texture than those found on either parent species.

Distribution

Bohemian knotweed is typically found in riparian areas and waste places. From the late 1800s, knotweeds have been introduced to new areas as an ornamental garden plant. The species has a worldwide distribution. It is considered by some as being a native hybrid of Japan. In Europe, it has been reported from the British Isles, Germany, France, northern Italy, Serbia, Bulgaria, Belgium, the Czech Republic, Slovakia, Romania, Ukraine, Scandinavia, and Switzerland. It is widespread in North America, and it has been discovered in Chile. It has also been found in Australia.

Management

In some areas, Bohemian knotweed is classified as an invasive species and a noxious weed. It is illegal to transport and sell in multiple US states, including Minnesota, Washington, and Wisconsin. Mechanical control and hand pulling are ineffective. Repeat herbicide application through spraying leaves and injecting stems is the best method. The beetle ''

Gallerucida nigromaculata ''Gallerucida'' is a genus of skeletonizing leaf beetles in the family Chrysomelidae. There are at least 19 described species in ''Gallerucida''. They are found in Indomalaya and eastern Asia. Species These 19 species belong to the genus ''Gall ...

'' has been considered to have potential as a biological control.

References

{{Taxonbar, from=Q12032320, from2=Q3064789, from3=Q49604659 Plants described in 1983 Flora of Japan Hybrid plants Garden plants Polygonoideae