Lycopus europaeus
Environmental Weed (2024)
Common names
Gypsywort
Biostatus
Exotic
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Simplified description
Mint-like plant, up to 1 m tall, with square stems, toothed paired leaves and tiny white or pale mauve flowers produced in groups above each pair of leaves in the upper stem, but no minty smell when crushed.
Flower colours
Purple, Red/Pink, White
Detailed description
Perennial herb. Stem hairy, to c. 1 m tall. Lvs shortly petiolate or sessile. Lamina 3-8.5 × 1-3 cm, ovate-lanceolate to elliptic, deeply crenate-serrate, hairy at first, becoming glabrous or nearly so; basal area with narrow-oblong or linear-oblong lobes extending to midrib; apex ± acuminate. Upper lvs and bracts smaller, without basal lobes, hairy, especially on veins below. Calyx c. 3 mm long, hairy; teeth > tube, lanceolate-acuminate. Corolla 3.5-4 mm long, white with purple spots on lower lip and in throat. Nutlets 1.2-1.3 mm long, broad-obovoid, glandular and swollen on anterior face, with margin clearly delimited.
Similar taxa
Superficially similar to mints (Mentha spp.) but lacking the characteristic smell of those plants.
Distribution
Abundant in the Waikato and Rotorua Lakes, few sites in Northland, Auckland and in Westland near Haast.
Habitat
Lake and river margins, drains and swamps, often growing at the base of raupo and tall sedges.
Conservation status
Not applicable
Detailed taxonomy
Family
Lamiaceae
Ecology
Flowering
Summer and autumn
Fruiting
Summer and autumn
Year naturalised
1940
Origin
Europe, cold temperate Asia
Reason for introduction
Possibly as a herbal plant
Control techniques
Rarely controlled, but can be controlled manually, mechanically or herbicidally depending on situation.
Life cycle and dispersal
Seed dispersed by water, footwear or contaminated machinery.
Wetland plant indicator status rating
Information derived from the revised national wetland plant list prepared to assist councils in delineating and monitoring wetlands (Clarkson et al., 2021 Manaaki Whenua – Landcare Research Contract Report LC3975 for Hawke’s Bay Regional Council). The national plant list categorises plants by the extent to which they are found in wetlands and not ‘drylands’. The indicator status ratings are OBL (obligate wetland), FACW (facultative wetland), FAC (facultative), FACU (facultative upland), and UPL (obligate upland). If you have suggestions for the Wetland Indicator Status Rating, please contact: [Enable JavaScript to view protected content]
OBL: Obligate Wetland
Almost always is a hydrophyte, rarely in uplands (non-wetlands).
Other information
Environmental Weed (2024)
This plant is named in a list of 386 environmental weeds in New Zealand 2024 prepared by DOC. 759 candidate species were considered for inclusion on this new comprehensive list of environmental weeds in New Zealand. The species considered were drawn from published lists of weed species, lists of plants that must be reported or managed by law if observed, existing national and regional programmes and agreements for pest management, and species already managed by the Department of Conservation (DOC). Candidate species were then assessed to see if they were fully naturalised and whether they have more than minor impacts in natural ecosystems. Read the full report here.
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
LYCEUR
Referencing and citations
References and further reading
Webb, C.J.; Sykes, W.R.; Garnock-Jones, P.J. (1988). Flora of New Zealand Volume 4: Naturalised pteridophytes, gymnosperms, dicotyledons. Botany Division, DSIR, Christchurch.
Johnson PN, Brooke PA (1989). Wetland plants in New Zealand. DSIR Field Guide, DSIR Publishing, Wellington. 319pp.
Champion et al (2012). Freshwater Pests of New Zealand. NIWA publication. http://www.niwa.co.nz/freshwater-and-estuaries/management-tools/identification-guides-and-fact-sheets/freshwater-pest-species
Attribution
Factsheet prepared by Paul Champion and Deborah Hofstra (NIWA). Features description from Webb et al., (1988).