Ashleaf maple	Status LU: established. 1st record: LU <1825, ITW <1875
	Eschen-Äerchen	Status Eur.: established. 1st record: UK 1688
	Erable negundo	RA: ISEIA: C1. Harmonia+: 0,23
	Eschen-Ahorn	Wikipedia: | Wikispecies: | CABI
	Vederesdoorn	Back to the list of neophytes

Report the species

→ Report Acer negundo to the National Museum of Natural History.

Brief description

Acer negundo L. is reported to prefer moist, eutrophic and warm conditions. It readily colonises resource-rich riparian forests in Central and Southern Europe (e.g. Salicion albae and Alno-Padion). Young trees prefer moist sites, but become drought tolerant once well established. Seeds are easily dispersed by wind and running water over long distances.

In Central Europe, box-elder is tolerant to flooding and is especially competitive in wide floodplains where vegetative regrowth can be impressive. However, in the absence of flooding, it is usually replaced in the course of succession by more shade-tolerant species. In optimal conditions, its permanent and fast vegetative regrowth leads to the formation of dense clones and to the exclusion of other tree species (Salix alba) and herbaceous plants. It favours replacement of softwood by hardwood tree species and makes a threat for this endangered habitat. A more invasive behaviour is likely to be observed in the future due to climate warming (Branquart et al. 2010).

Status and distribution in Luxembourg

The who oldest reference to Acer negundo L. in Luxembourg are found in the floras of Krombach and Koltz: Krombach (1875: 66) reports it being grown in parks and avenues, while Koltz (1875:  27) mentions Acer negundo as “Introduced at the beginning of this century under the name of green maple [Orig.: érable vert] and subspontaneous in the vicinity of Ansembourg”. We thus deduct the 1st record as anterior to 1825 and the 1st record in the wild as anterior to 1875 (Ries & Krippel 2021).

Acer negundo as a cultivated species was first recorded in 1948 by Jos. Witry in a park in Rumelange (Specimen № 51452, MNHNL 2000-).

The first documentation of Acer negundo in the wild dates from 1958. It was recorded on 1st June 1958 by Léopold Reichling at Stromberg, a wooded hill in the municipality of Schengen (MNHNL 2000-).

14 observations are accessible via the MNHNL-mdata portal (MNHNL, iNaturalist & GBIF 2019).

The species is expanding into the territory of the flora (Lambinon & Verloove 2012: 461).

Risk assessment

ISEIA protocol

C1 (1+1+1+1) (Ries et al. 2013: 18).

Harmonia+ protocol

Overall risk score 0,23 = (Overall Invasion score 0,53 x Overall Impact score 0,43) (Ries et al. 2020).

Worldwide distribution

Bibliography

• Branquart, E., S. Vanderhoeven, W. Van Landuyt, F. Van Rossum & F. Verloove, 2012. Harmonia database: Acer negundo L. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-10-23]
• CABI, 2019. Acer negundo L. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2019-11-26]
• 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-. Acer negundo L. 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 2018-01-08]
• MNHNL, iNaturalist & GBIF, 2019. Acer negundo L. 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 2019-09-06]
• 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]
• Welter A., J.Turk & J. Trossen, 2008. Les arbres introduits au Luxembourg. Inventaire des essences arborescentes non indigènes de pleine terre présentes sur le territoire du Grand-Duché de Luxembourg. Ferrantia 53, Musée national d’histoire naturelle, Luxembourg, ISSN 1682-5519, 111 pp.