Pueraria montana var. lobata | Kudzu
Regulated invasive species of Union concern under the European Regulation on the prevention and management of the introduction and spread of invasive alien species [1143/2014].
Invasive species - risk of Medium Impact
Introduction pathways - 1
Escape from Confinement
Introduction pathways subclass - 1
NAPRA Ireland risk assessed
Fast-growing perennial semi-woody twining vine. Stems hairy and can reach 30m long and 30cm thick (GISD, 2015). Alternate compound leaves are made up of 3 leaflets and both sides are hairy (GSID, 2015). Flowers borne in long hanging panicles from June to September (EPPO, 2007). Pea-like flowers are pink, purple or blue and strongly scented of grapes (EPPO, 2007). Seed pods are brown and hairy. Root system is large and tuberous. Tubers can be 2m long and extend 5m deep (EPPO, 2007).
Likes warm wet climates with rainfall >1000mm per annum and summers temperatures >27°C (Q-bank, 2017). Fast-growing and can achieve 15m per season (Q-bank, 2017). Forms mats 2m thick (PIER, 2007) enabling it to completely smother trees and shrubs, blocking light to everything underneath it and out-competing native vegetation by monopolising resources. Does well in full sun but can survive in partial shade. Tolerates a wide range of soil types but prefers moist and fertile conditions (GISD, 2015). Fixes nitrogen in the soil thus altering the chemical balance of the ecosystem (EPPO, 2006).
Reproduces by vegetative means. Stem nodes readily root when in contact with soil. Pollinated by insects but doesn't produce viable seed in non-native range (Q-bank, 2017).
Pathway and vector description
Most likely pathway of entry is through the purchase of plants for horticulture or agriculture (EPPO, 2007). Once established the plant readily spreads by vegetative means.
Mechanism of impact
There is currently an EU wide ban on the sale, growing and keeping of this plant (European Commission, 2017).
In open areas, monthly close mowing for several seasons should exhaust the rhizome and kill the plant (PIER, 2007).
Global Invasive Species Database (2015) describes control achieved by bulldozing followed by burning.
Can be difficult to control with chemicals due to the huge rhizomes, which can account for 50% of the plants biomass (GISD, 2015). Type of herbicide is dependant on many factors including age of plants, ease of access to location, proximity to water, presence of other plants. Repeat application will be necessary until all root crowns have been killed (EPPO, 2007). Efficacy of chemical application may be increased by prescribed burning in the spring (EPPO, 2007).
Close and prolonged grazing by cattle, pigs, goats or horses is effective in areas where access is possible and where livestock can reach all the plants (Rhoden et al., 1991 in EPPO, 2007).
Its natural habitat in Asia is broadleaf and mixed forestry (EPPO, 2007). Also found in pastures, gardens, wasteland, open woodland, and on roadsides, along railways and inland waterways (EPPO, 2007).
Introduced in USA, Canada, Central and South America, Africa, Oceania and parts of Asia. In Europe it is in Italy and Switzerland. In the USA it is only invasive in the southeast.
Native to China, Japan and Korea (EPPO, 2007).
Records submitted to Data Centre in 2021
The following map is interactive. If you would prefer to view it full screen then click here.
How can you help
Report any sightings to the National Biodiversity Data Centre. Do not purchase or plant in your garden. Dispose of any garden plants or weeds responsibly.
CABI (2007) Invasive Species Compendium. Datasheet report for Pueraria montana var. lobata (kudzu) http://www.cabi.org Site accessed 23 September 2017.
European and Mediterranean Plant Protection Organisation (EPPO) (2007) Datasheets on quarantine pests Pueraria lobata. Bulletin OEPP/EPPO Bulletin 37, 230–235. https://gd.eppo.int/taxon/PUELO/documents Site accessed 23 September 2017.
European and Mediterranean Plant Protection Organisation (EPPO) (2006) Report of a pest risk analysis Pueraria montana var. lobata. EPPO. Paris. https://gd.eppo.int/taxon/PUELO/documents Site accessed 23 September 2017.
European Commission. (2017). Invasive Alien Species of Union Concern. European Union, Luxembourg.
Global Invasive Species Database (GISD) 2015. Species profile Pueraria montana var. lobata. Available from: http://www.iucngisd.org/gisd/species.php?sc=81 Site accessed 23 September 2017.
PIER (2007). PIER Species Info - Pueraria montana var. lobata (Willd.) Maesen & S. M. Almeida, Fabaceae Pacific Islands Ecosystems at Risk. USA: Institute of Pacific Islands Forestry. http://www.hear.org/pier/species/pueraria_montana_var_lobata.htm Site accessed 24 September 2017.
Q-bank (2017) Q-bank factsheet Pueraria montana (Lour.) Merr. var. lobata (Willd.) Sanjappa & Pradeep – Kudzu. http://www.q-bank.eu/Plants/Factsheets/Pueraria_montana_lobata_EN.pdf Site accessed 23 September 2017.
Rhoden EG, Woldeghebriel A & Small T (1991) Kudzu as a feed for Angora goats. Tuskegee Horizons 2, 23.
At present Ireland's climate is probably too cool for establishment.