Giant hogweed	Status LU: established. 1st record: LU ~1934, ITW 1980.
	Rise-Biereklo	Status Eur.: established. 1st record: UK 1817. IAS of EU concern (2017).
	Berce du Caucase, berce de Mantegazzi	RA: ISEIA: A3, Black List. Harmonia+: 0,64.
	Riesen-Bärenklau, Herkulesstaude	Wikipedia: | Wikispecies: | CABI
	Reuzenberenklauw, Perzische berenklauw	Back to the list of neophytes

Brief description

Heracleum mantegazzianum Somm. et Lev. inhabits moist and nutrient-rich soils in ruderal places, along roadsides, riverbanks and forest margins, in abandoned or neglected grasslands and in tall-herb communities. It is poorly represented in old successional stages but can occur in open alluvial forests. It usually invades sites with a low management intensity. Seeds are usually dispersed in the vicinity of mother plants except when growing near rivers. In that case, they may be transported over several kilometres.

The enormous height and leaf area of the giant hogweed enable it to overtop most indigenous herbaceous plant species typical of early stages of natural successions. It may form dense populations that absorb up to 80% of the incoming light and out-compete most light-demanding species. However, its abundance decreases in old successional stages due to competition with trees. Besides the ecological problems, tall invasive hogweed species also represent a serious health hazard for humans. The plant exudes a clear watery sap, which contains several photosensitising furanocoumarins. Upon contact with human skin and in combination with ultraviolet radiation, these compounds cause severe burning of the skin (Branquart et al. 2010).

IAS of Union concern

In 2017, Heracleum mantegazzianum Somm. et Lev. was added to the list of invasive alien species of Union concern (Anonymous 2017) which implies that member states shall take all necessary steps to prevent it’s unintentional introduction or spread.

Status and distribution in Luxembourg

The melliferous plant Heracleum mantegazzianum Somm. et Lev. was introduced to Luxembourg by the Luxembourg botanist Edmond Joseph Klein (1866-1942) in the 1930s. In 1935, a flowering giant hogweed made his front garden in avenue Grande-Duchesse-Charlotte in Luxembourg City an attraction for naturalists and beekeepers, who collected seeds to grow the plant in their gardens or near their beehives (Reichling 2008). This explains why many large populations of this plant in Luxembourg are a result of plantation by beekeepers. As the species is perennial and needs at least one year to develop before flowering, we can assume that Klein introduced seeds of the species to Luxembourg before 1934 and sowed them in or before 1934, which we consider the first record of the species in Luxembourg.

The south-west Asian species was first documented in 1980 near Garnich by Léopold Reichling (1921-2009): “A colony of about a hundred feet is known to be located N of the Luxembourg-Arlon railway line east of the Garnich-Windhof road. Recent road works have reduced its importance.” (Reichling 1990: 62; MNHNL 2000-). Cultivated for ornamental use in parks and gardens. Subspontaneous or naturalized, quite rare, mostly widespread in urban areas and along highways; often abundant in its stations. Introduced in Brussels in the 1930s, this species has experienced, especially since the 1980s, a strong expansion in the Flora territory, as in other regions of Europe (Lambinon & Verloove 2012: 524).

Giant hogweed was getting very common and widespread in Luxembourg during the period 2000-2010. It generally occurred in small clusters along river banks, several major rivers of Luxembourg having been affected. Sometimes the species formed dense stands along rivers, bicycle ways and rail roads or on waste land. Since 2008 many stakeholders are involved in control measures resulting in the decline of the species. This might result in the downgrade of the ISEIA-code of the species (A3) in future risk assessments.

End of 2023, 560 records of this melliferous species were listed in the MNHNL-mdata online portal (MNHNL, iNaturalist & GBIF 2019). As is the case for many species, the shown map doesn’t reflect the actual status of the species, but its historical distribution accumulated in time.

Hybrids and other taxa

It is known that Heracleum mantegazzianum can hybridise with H. sphondylium (Heracleum mantegazzianum Somm. and Lev. × H. sphondylium L. var. dissectum Le Gall).

In Luxembourg, the hybrid has so far been detected 3 times in the north of the country: Harlange in 2014 (Krippel & Colling 2016: 37), Kuborn in 2016 (Krippel et al. 2018: 64), and Nothum in 2018 (Krippel et al. 2020: 39).

Other taxa that are more or less neighbouring are also sometimes cultivated for ornamental purposes. Thus, the subspontaneous state of Heracleum laciniatum Hornem. (Syn. Heracleum giganteum Hort.) has been reported in the territory of the Flora, but it has been hypothesized that they would actually be hybrids of Heracleum mantegazzianum × sphondylium. The taxonomy of large Asian Heracleum species introduced into Europe should be re-examined (Lambinon & Verloove 2012: 524).

Management

Since 2008, the Luxembourg Water Management Authority is systematically controlling giant hogweed on the river banks of the major rivers of Luxembourg and is running special units for this purpose.

The Upper-Sûre Nature Park in the north-west of Luxembourg (Ardennes) runs a monitoring and management plan on giant hogweed since 2009 in the frame of the national action plan “Heracleum mantegazzianum” (Krippel & Richarz 2013). The inventories show a prevalence of H. mantegazzianum populations in two valleys i.e. Harelerbaach and Dirbech, where the plants are growing predominately on riversides and alluvial meadows. Since 2009, the management plan is annually reviewed and consequently executed in the Upper-Sûre region. Giant hogweed is controlled by root cutting and, in the case of flowering plants, by umbel removal. These simple mechanical methods give excellent results, but have to be continued for several years, until the soil seed bank is depleted, especially in the valleys of the Surbich and Harelerbaach (Krippel & Colling 2014, 2016; Krippel et al. 2018: 64). At Tutschemillen, this invasive exotic species remains despite its regular elimination by the services of the Haute-Sûre Nature Park (Krippel et al. 2020: 39).

Since 2009, after a sensitisation campaign by the Nature and Forest Agency, several foresters systematically control giant hogweed in their areas.

Since 2010, the city of Luxembourg systematically controls hogweed on its grounds, especially along the Alzette river.

In 2012, three workers of the national railway company CFL were burned by giant hogweed while cleaning up an overgrown area of a railway station. A survey of several neophyte species on the national railway network (Pfeiffenschneider et al. 2014d) resulted in four sites identified with Heracleum, which were subsequently controlled in the same year.

Action plan

An action plan regarding Giant Hogweed has been published in 2020:

→ Finalised Action Plan for Heracleum mantegazzianum (Pfeiffenschneider & Hoppe 2020)

Giant hogweed auger

In order to facilitate the control, an auger was developed by a Dutch company (https://www.eijkelkamp.com). The giant hogweed auger removes the roots of the giant hogweed ergonomically and effectively, preventing the plant from germinating again. For effective control, it is advisable to remove the roots from the non-flowering specimens both in the spring before flowering and in the autumn. The auger body is 33 cm long, with a diameter of 89 mm. The one-piece auger has a total length of 111.4 cm. The auger is easily emptied using a bent spatula.

Burn cases in Luxembourg

The Department of Ecology of the National Museum of Natural History made two surveys among physicians in Luxembourg on burns caused in 2008 and in 2011 and 2012 (cf. Ries et al. 2013). Results showed that there have been at least 60 cases of burns in 2011 and 2012, while the previous survey back in 2008 resulted in no feedback on burn cases. These features are in line with the ongoing spread of the species in that period in Luxembourg. Most victims were aged between 18 and 60 and have been affected by burns in summer. The severity of burns ranged from not severe to medium.

Special observations:

• When controlling giant hogweed during full flowering, the dust generated during removal of the flowers can penetrate between the protective clothing and the throat of a worker and cause a line or strip of burned skin (Adm. de la gestion de l’eau, personal communication, 2013).
• In 2013, children suffered burns when playing with the previous year’s withered stems in early spring (Danièle Dammé, personal communication, May 20, 2014).

Useful documents

• National sensitisation campaign in Luxembourg in 2014:
  – Flyer in French and German [pdf 1,7 MB]
  – Poster in French and German [pdf 1 MB]
• Basic information poster about giant hogweed (English, Deutsch, Français, Nederlands) [jpg 3,5 MB]
• The giant hogweed Best Practice Manual (English, Deutsch, Français) [pdf 2,5 MB]

Risk assessment

ISEIA protocol

A3 (3+3+2+3) = Black List (Ries et al. 2013: 18).

Harmonia+ protocol

Overall risk score 0,64 = (Overall Invasion score 0,77 x Overall Impact score 0,83) (Ries et al. 2020).

Worldwide distribution

Bibliography

• Albers, M., S. Kohn, J. Steng & M. Pfeiffenschneider, 2001. Problematik der Bioinvasion. Kartierung von Japan-Knöterich, Riesenbärenklau und Indischem Springkraut an Woltz, Clerve und Wiltz. Ergebnisse der Kartierung. Studie des Büros ERSA im Auftrag von: Administration des eaux & forêts, arrondissement nord. August 2001. 7S. + Anhang.
• Anonymous, 2017. Commission implementing regulation (EU) 2017/1263 of 12 July 2017 updating the list of invasive alien species of Union concern established by Implementing Regulation (EU) 2016/1141 pursuant to Regulation (EU) No 1143/2014 of the European Parliament and of the Council. Official Journal of the European Union L 182: 37-39 (13.7.2017).
• Branquart, E., S. Vanderhoeven, W. Van Landuyt, F. Van Rossum, F. Verloove & A. Vervoort, 2010. Harmonia database: Heracleum mantegazzianum Somm. et Lev.. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-10-11]
• CABI, 2019. Heracleum mantegazzianum. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2020-03-02]
• Glesener, B., M. Pfeiffenschneider & C. Ries, 2009. Die Verbreitung von Impatiens glandulifera, Fallopia japonica, F. sachalinensis, F. ×bohemica und Heracleum mantegazzianum entlang der Hauptfließgewässer Luxemburgs. Bull. Soc. Nat. luxemb. 110 : 69-73. (pdf)
• Krippel, Y. & F. Richarz, 2013. Verbreitung und Management von Heracleum mantegazzianum Somm. et Lev. (Apiaceae, Spermatophyta) in der Obersauerregion in Luxemburg. Bull. Soc. Nat. luxemb. 114: 3-13. (pdf)
• Krippel, Y. & G. Colling, 2014. Notes floristiques. Observations faites au Luxembourg (2012-2013). Bull. Soc. Nat. luxemb. 115: 109-124.
• Krippel, Y. & G. Colling, 2016. Notes floristiques. Observations faites au Luxembourg (2014-2015). Bull. Soc. Nat. luxemb. 118: 27-51. [PDF 1.33 MB]
• Krippel, Y., T. Helminger & G. Colling, 2018. Notes floristiques. Observations faites au Luxembourg (2016-2017). Bull. Soc. Nat. luxemb. 120: 57-76. [PDF 265 KB]
• Krippel, Y., T. Helminger & G. Colling, 2020. Notes floristiques. Observations faites au Luxembourg (2018-2019). Bulletin Soc. Nat. luxemb. 122 : 29-55. [PDF 132 KB]
• Lambinon J. & F. Verloove, 2012. Nouvelle flore de la Belgique, du grand-duché de Luxembourg, du Nord de la France et des régions voisines. Sixième édition. Avec la collaboration de L. Delvosalle, B. Toussaint, D. Geerinck, I. Hoste, F. Van Rossum, B. Cornier, R. Schumacker, A. Vanderpoorten et H. Vannerom. Jardin botanique national de Belgique, Meise. CXXXIX + 1195 pp. ISBN : 9789072619884.
• MNHNL, 2000-. Heracleum mantegazzianum Somm. et Lev. in Recorder-Lux, database on the natural heritage of the Grand Duchy of Luxembourg. Musée national d’histoire naturelle, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-10-11]
• MNHNL, iNaturalist & GBIF, 2019. Heracleum mantegazzianum Somm. et Lev. in MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-10-11]
• Pfeiffenschneider, M., 2001. Problematik der Bioinvasion. Nationales Inventar von Riesenbärenklau, Indischem Springkraut und exotischen Knötericharten. Ergebnisse einer Umfrage und Konzept zur Bekämpfung der Riesenbärenklaubestände. Studie des Büros ERSA im Auftrag von: Administration des eaux & forêts, Service de la conservation de la nature, November 2001. 23 S. + Anhang, Luxembourg.
• Pfeiffenschneider, M., 2007. Über die Verbreitung von Heracleum mantegazzianum, Impatiens glandulifera, Fallopia japonica und F. sachali­nensis entlang der Gewässer Obersauer, Woltz, Clerve, Wiltz und ihrer Nebengewässer (Luxemburg). Bull. Soc. Nat. luxemb. 108 : 7-10. (pdf)
• Pfeiffenschneider, M., 2008. Neophyten in Luxemburg – Projekt Bioinvasion 2007. Arbeitsbericht. 18 S. (pdf)
• Pfeiffenschneider, M. & F. Hoppe, 2020. Plan d’action pour espèces exotiques envahissantes au Grand-Duché de Luxembourg : Berce géante, Heracleum mantegazzianum Sommier & Levier 1895. Version du 2020-09-23. Administration de la nature et des forêts, Luxembourg. 20 pp
• Pfeiffenschneider, M., P. Gräser & C. Ries, 2014a. Distribution of selected neophytes along the main rivers of Luxembourg. Poster in 2 parts at XXXIe réunion annuelle des collaborateurs scientifiques du Musée national d’histoire naturelle Luxembourg, 15.03.2014. (pdf 2,7 MB)
• Pfeiffenschneider, M., P. Gräser & C. Ries, 2014b. Distribution of selected neophytes along the national railway network of Luxembourg. Poster at XXXIe réunion annuelle des collaborateurs scientifiques du Musée national d’histoire naturelle Luxembourg, 15.03.2014. (pdf 1,4 MB)
• Pfeiffenschneider, M., P. Gräser & C. Ries, 2014c. Distribution of selected neophytes along the main rivers of Luxembourg. Bull. Soc. Nat. luxemb. 115: 101-108. [PDF 3668 KB]
• Pfeiffenschneider, M., P. Gräser & C. Ries, 2014d. Distribution of selected neophytes along the national railway network of Luxembourg. Bull. Soc. Nat. luxemb. 115: 95-100. [PDF 1457 KB]
• Pfeiffenschneider, M. & M. Owaller, 2000. Kartierung von Japan-Knöterich, Riesenbärenklau und Indischem Springkraut an der Obersauer. Theoretische Grundlagen und Ergebnisse der Kartierung. Studie des Büros ERSA im Auftrag von: Administration des eaux & forêts, acrrondissement nord. August 2000. 37S. + Anhang, Luxembourg.
• Reichling, L., 1990. Observations floristiques au Luxembourg 1980-1989. Bulletin de la Société des naturalistes luxembourgeois 90: 55-70. [PDF 808 KB]
• Reichling, L., 2008. Personal communication to C. Ries.
• Ries, C. & Y. Krippel, 2021. First records of 56 invasive alien vascular plants in Luxembourg. Bulletin de la Société des naturalistes luxembourgeois 123: 115-127. [PDF 241 KB]
• Ries, C., Y. Krippel, M. Pfeiffenschneider & S. Schneider, 2013. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of non-native vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 114: 15-21. [PDF 652 KB]
• Ries, C., Y. Krippel & M. Pfeiffenschneider, 2020. Risk assessment after the Harmonia+ protocol of invasive alien vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 122: 197-205. [PDF 132 KB]
• Ries, C, Y. Steil & M. Pfeiffenschneider, 2013. Survey amongst physicians in Luxembourg on burns caused in 2011 and 2012 by the giant hogweed (Heracleum mantegazzianum SOMMIER & LEVIER, Apiaceae). Poster at XXXe réunion annuelle des collaborateurs scientifiques du Musée national d’histoire naturelle Luxembourg, 16.03.2013. (pdf 1,2 MB)

 Page content last updated on 2024-07-31. Last proofread by Caroline Grounds on 2019-11-11.

	Japanese Knotweed	Status LU: established. 1st record: LU 1849, ITW <1872.
	Japanescht Knuetkraut	Status Eur.: established. 1st record: NL 1847.
	Renouée du Japon, renouée bambou	RA: ISEIA: A3 – Black List. Harmonia+: 0,63
	Japanischer Staudenknöterich, J. Flügelknöterich	Wikipedia:   | Wikispecies: | CABI
	Japanse duizendknoop	Back to the list of neophytes

Brief description

Like other Asiatic knotweeds, Japanese knotweed colonises a wide range of environments, with a predilection for moist and nitrogen-rich soils. It prefers sunny places or semi-shaded habitats. This pioneer plant proliferates both in ruderal and semi-natural habitats, including riparian areas and open forests. It doesn’t produce any seed and reproduces clonally. Stem and rhizomes may easily split into small pieces; fragments are able to regenerate a plant, provided a node is present. Transport of garden waste and soil contaminated with rhizomes are the major dispersal modes. Where the plant is widely consolidated on river banks it is also spread by floods and can easily colonise downstream (Branquart et al. 2010).

Fallopia japonica is able to monopolise space and to form dense and persistent populations. It can outcompete most native herbaceous plant species thanks to early seasonal development, high growth rate and productivity, abundant leaf cover, allelochemical production and clonal spread associated with an extraordinarily high rate of proliferation of below-ground organs. It also decreases soil bulk density and pH, increases organic matter content and enhances nutrient cycling rates, probably due to nutrient uplift. Its development reduces plant and invertebrate species diversity, alters habitats for fish and wildlife, changes light and energy conditions of the ecosystem, and favours river bank erosion during the winter. Prolific rhizome and shoot growth can damage foundations, walls, pavements, and drainage works, and causes flood hazards by increasing resistance to water flow and damaging flood prevention structures (Branquart et al. 2010).

Uncertain status of Fallopia japonica in Luxembourg

Identification of knotweed species is not always easy, especially the very similar Japanese knotweed (Fallopia japonica) and Bohemian knotweed (Fallopia × bohemica), a hybrid between Japanese knotweed and Sakhalin knotweed (Fallopia sachalinensis). Until recently, Japanese knotweed was considered much more widespread in Luxembourg than Bohemian knotweed. During the field trip of the Neobiota 2016 conference in September 2016, knotweed populations near Michelau that were so far considered as F. japonica were identified by specialists as F. × bohemica.

To assess the accuracy of the data collected to date, the Department of Ecology of the Museum carried out a small survey in 2017:  31 specimens of knotweed populations were collected across the country, described and filed in the museum’s herbarium. Genetic analysis of the samples in the museum’s lab showed that in Luxembourg F. × bohemica is more common than Fallopia japonica. The data of both taxa need to be updated in the Recorder-Lux database (MNHNL, 2000-).

Status and distribution in Luxembourg

Koltz (1875: 127) reports that Fallopia japonica (Houtt.) Ronse Decr. (under its synonym Polygonum cuspidatum Sieb. & Zucc.) was introduced in 1849 in Luxembourg by Philipp Franz von Siebold (1796–1866)¹ in the park of the Royal residence (castle) in Walferdange, two years after Siebold introduced the species from Japan² to The Netherlands (Bailey & Conolly 2000: 94), and one year before the species was sent to the Royal Botanical Gardens at Kew, UK, in 1850 (Bailey & Conolly 2000: 97, CABI 2021).

This is inline with Eugène Fischer (1821-1903), who reports that Fallopia japonica (Houtt.) Ronse Decr. was introduced in Luxembourg about 20 years before 1872 (Fischer 1872: 89). He lists the species under its synonym Polygonum cuspidatum Sieb.³ Some twenty years after its introduction, Fischer already had a feeling of the potential of this species as an invasive species: “Siebold’s knotweed […], originating from Japan, was introduced as ornamental crops in the Grand Duchy around 1852. It is very tractable, remarkable for its great development and its great rusticity, which allows it to grow in all terrain and at all exposures. It multiplies and is maintained with such ease that it returns without culture and care to some gardens and nearby. I am inclined to believe that it will now remain in the country as a subspontaneous plant.”⁴

Around 1873-1875, Japanese knotweed (Polygonum cuspidatum) was quite common in Luxembourg, cultivated in gardens and appeared sometimes subspontaneously in their vicinity (Koltz 1873: 142; Krombach 1875: 379).

The first herbarium specimen of the species in Luxembourg dates from 1947. On 11th July 1947, François Léon Lefort (1917-1975) collected a specimen near the Carmel in Luxembourg City (Specimen № 22229, MNHNL 2000-).

According to Lambinon & Verloove (2012: 193), the species occurs on wasteland, embankments, stream banks, forest edges. Sometimes grown for ornamental purposes in parks (formerly also as fodder). Fairly common to fairly rare (AC-AR) and naturalised in all flora districts, very invasive.

Currently, 1140 records of the species and its subspecies are accessible through the MNHNL-mdata portal (MNHNL, iNaturalist & GBIF 2019). As outlined in the section above, these data have to be revised, as most of these records could have been misidentified, which is why we describe both taxa together in the following section.

Importance and distribution of Japanese and Bohemian knotweed in Luxembourg

Bohemian and Japanese knotweed are common and widespread invasive neophytes in Luxembourg. They build huge colonies along riparian ecosystems, several major rivers of Luxembourg being affected. They regularly grow in small patches along roadsides and in waste grounds, most of these places having been “contaminated” by people getting rid of knotweed clippings from their gardens. Examples can be seen along the main road leaving Luxembourg City in the direction of Echternach. Nurseries and garden designers sometimes contribute to the spread of knotweed in gardens and public green spaces by using contaminated compost.

Risk assessment

ISEIA protocol

A3 (3+3+3+3) = Black List (Ries et al. 2013: 18).

Harmonia+ protocol

Overall risk score 0,63 = (Overall Invasion score 0,84 x Overall Impact score 0,75) (Ries et al. 2020).

Worldwide distribution

Leaflet

In early spring 2020 the Department for the Environment of the Luxembourg Ministry for environment, climate and sustainable development edited leaflets in German and French about Fallopia japonica, in co-operation with the National Museum of Natural History and efor-ersa ingénieurs-conseils. They can be downloaded here in PDF format (~ 4 MB each).

  

Bibliography

• Albers, M., S. Kohn, J. Steng & M. Pfeiffenschneider, 2001. – Problematik der Bioinvasion. Kartierung von Japan-Knöterich, Riesenbärenklau und Indischem Springkraut an Woltz, Clerve und Wiltz. Ergebnisse der Kartierung. – Studie des Büros ERSA im Auftrag von: Administration des eaux & forêts, arrondissement nord. August 2001. 7S. + Anhang.
• Bailey, J.P. & A.P. Conolly, 2000. Prize-winners to pariahs – A history of Japanese Knotweed s.l. (Polygonaceae) in the British Isles. Watsonia. 23: 93–110.[PDF]
• Branquart, E., S. Vanderhoeven, W. Van Landuyt, F. Van Rossum, F. Verloove & A. Vervoort, 2010. Harmonia database: Fallopia japonica (Houtt.) Ronse Decr. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-10-09]
• CABI, 2021. Fallopia japonica. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2021-03-04]
• Fischer, E., 1872. Les plantes subspontanées et naturalisées de la flore du grand-duché de Luxembourg. Publications de l’Institut royal grand-ducal de Luxembourg, section des sciences naturelles et mathématiques XII: 1-115. Imprimerie V. Buck, Luxembourg.
• Glesener, B., M. Pfeiffenschneider & C. Ries, 2009. Die Verbreitung von Impatiens glandulifera, Fallopia japonica, F. sachalinensis, F. ×bohemica und Heracleum mantegazzianum entlang der Hauptfließgewässer Luxemburgs. Bull. Soc. Nat. luxemb. 110 : 69-73. (pdf)
• Krombach, J.-H.-G., 1875. Flore du grand-duché de Luxembourg. Plantes phanérogames. 564 p. Luxembourg, Imprimerie Joris.
• Lambinon J. & F. Verloove, 2012. Nouvelle flore de la Belgique, du grand-duché de Luxembourg, du Nord de la France et des régions voisines. Sixième édition. Avec la collaboration de L. Delvosalle, B. Toussaint, D. Geerinck, I. Hoste, F. Van Rossum, B. Cornier, R. Schumacker, A. Vanderpoorten et H. Vannerom. Jardin botanique national de Belgique, Meise. CXXXIX + 1195 pp. ISBN : 9789072619884.
• MNHNL, 2000-. Fallopia japonica (Houtt.) Ronse Decr. in Recorder-Lux, database on the natural heritage of the Grand Duchy of Luxembourg. Musée national d’histoire naturelle, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-09-05]
• MNHNL, iNaturalist & GBIF, 2019. Fallopia japonica (Houtt.) Ronse Decr. in MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-09-05]
• Pfeiffenschneider, M., 2001. – Problematik der Bioinvasion. Nationales Inventar von Riesenbärenklau, Indischem Springkraut und exotischen Knötericharten. Ergebnisse einer Umfrage und Konzept zur Bekämpfung der Riesenbärenklaubestände. – Studie des Büros ERSA im Auftrag von: Administration des eaux & forêts, Service de la conservation de la nature, November 2001. 23 S. + Anhang, Luxembourg.
• Pfeiffenschneider, M., 2007. Über die Verbreitung von Heracleum mantegazzianum, Impatiens glandulifera, Fallopia japonica und F. sachali­nensis entlang der Gewässer Obersauer, Woltz, Clerve, Wiltz und ihrer Nebengewässer (Luxemburg). Bull. Soc. Nat. luxemb. 108 : 7-10. (pdf)
• Pfeiffenschneider, M., 2008. Neophyten in Luxemburg – Projekt Bioinvasion 2007. Arbeitsbericht. 18 S. (pdf)
• Pfeiffenschneider, M. & M. Owaller, 2000. – Kartierung von Japan-Knöterich, Riesenbärenklau und Indischem Springkraut an der Obersauer. Theoretische Grundlagen und Ergebnisse der Kartierung.. – Studie des Büros ERSA im Auftrag von: Administration des eaux & forêts, acrrondissement nord. August 2000. 37S. + Anhang, Luxembourg.
• Ries, C. & Y. Krippel, 2021. First records of 56 invasive alien vascular plants in Luxembourg. Bulletin de la Société des naturalistes luxembourgeois 123: 115-127. [PDF 241 KB]
• Ries, C., Y. Krippel & M. Pfeiffenschneider, 2020. Risk assessment after the Harmonia+ protocol of invasive alien vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 122: 197-205. [PDF 132 KB]
• Ries, C., Y. Krippel, M. Pfeiffenschneider & S. Schneider, 2013. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of non-native vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 114: 15-21. [PDF 652 KB]

 Page content last updated on 2023-02-27. Last proofread by Caroline Grounds on 2019-11-18.

1. In 1851 Philipp Franz von Siebold became an honorary member of the “Société naturelle dans le Grand-Duché de Luxembourg”, and in 1852 Commander of the Order of the Oak Crown [Ordre de la Couronne de chêne] (Luxembourg/Netherlands). [Source, PDF][↩]
2. Philipp Franz von Siebold was a German doctor who lived and worked for the Dutch on the Japanese island of Deshima[↩]
3. According to the Plants of the World online the correct/complete name of this synonym should be Polygonum cuspidatum Siebold & Zucc.[↩]
4. Original text: « La renouée de Siebold […], originaire du Japon, a été introduite dans les cultures ornementales du Grand-Duché vers 1852. Elle est très traçante, remarquable par son grand développement et sa grande rusticité qui lui permet de croître dans tous les terrains et à toutes les expositions. On la voit se multiplier et se maintenir avec tant de facilités qu’elle revient sans culture et sans soins dans quelques jardins et à proximité. Je suis porté à croire qu’elle se maintiendra dorénavant dans le pays comme plante subspontanée. » (Fischer 1872: 89)[↩]