Epilobium chionanthum
Common name
marsh willowherb
Synonyms
None
Family
Onagraceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Herbs - Dicotyledons other than Composites
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.
EPICHI
Chromosome number
2n = 36
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – an interim threat classification status has not been assessed by the NZTCS panel.
- Conservation status of New Zealand indigenous vascular plants, 2017 . 2018. Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley. Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Not Threatened | Qualifiers: DP
Previous conservation statuses
2012 | Not Threatened
2009 | Not Threatened | Qualifiers: DP
2004 | Gradual Decline
Distribution
Endemic. New Zealand: North, South and Chatham Islands.
Habitat
In swamps and wet swards of grasses or sedges, beside lakes or rivers, and in bogs. Lowland to upland, mostly below 900m altitude.
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).
Features
Loosely clumped perennial herb up to 0.75 m tall, producing numermous leafy stolons above and below ground; stems often reddish, mostly glabrous, strigulose along lines decurrent from the margins of the petioles below and all round above and in the inflorescence, more rarely pubescent all round to the base. Leaves much shorter than the internodes they subtend, mostly opposite, a few alternate in the inflorescence, dull green, paler beneath, the lateral veins quite prominent, 3-4 on each side of the midrib, subsessile; lamina 12-40 × 7-15 mm, elliptic to ovate, acute at the apex, narrowly cuneate to rounded at the base, margins serrulate, usually with 7-14 often obscure teeth on each side. Inflorescence erect. Flowers erect. Ovary 10-20 mm long, investiture mixed glandular and strigulose, on a pedicel 2-7 mm long. Floral tube 1.0-1.7 × 1.4-1.8 mm. Sepals 4.0-5.2 × 1.5-1.7 mm, slightly keeled, indumentum of mixed glandular and strigulose hairs. Petals 6.0-11.0 × 4.5-6.0 mm, notch 0.8-1.3 mm deep, white, often flushed pink at fertilisation. Stamens filaments white, of two types: long (2.0-3.5 mm long) and short (0.8-1.3 mm long), Anthers 1.3-1.5 × 0.6-0.7 mm, bright yellow. Style 5.2-9.0 mm long, white, stigma 1.0-2.0 x 0.9-2.0 mm, globose, obscurely 4-lobed, held above anthers in early anthesis. Capsule 40-60 mm long on a pedicel 12-28 mm long, moderately to densely strigulose and glandular. Seeds 1.4-1.8 mm long, dark brown, narrowly obovate to obovate, finely reticulate to reticulate-mamillate; coma 7.5-11.0 mm long, orange to orange-brown, persistent.
Similar taxa
Other Epilobium species. E. chionanthum has large flowers and hairless, dull green leaves with tiny teeth.
Flowering
October - March
Flower colours
Red/Pink, White
Fruiting
November - April
Life cycle
Minute pappate seeds are wind dispersed (Thorsen et al., 2009).
Propagation technique
Easy from rooted pieces and fresh seed. Tends to be short-lived and resents competition.
Threats
At risk from wetland drainage and the spread of invasive weeds. Some populations have been destroyed by coastal development.
Etymology
epilobium: From the Greek epi- ‘upon’ and lobos ‘a pod’, the flowers appearing to be growing on the seed pod.
chionanthum: Snowy-white flower
Where To Buy
Not commercially available.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange 28 August 2011. Description adapted from Raven & Raven (1976) and Webb & Simpson (2001).
References and further reading
Raven, P.H.; Raven, T.E. 1976: The genus Epilobium in Australasia. New Zealand DSIR Bulletin 216. Wellington, Government Printer.
Thorsen, M. J.; Dickinson, K. J. M.; Seddon, P. J. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285-309
Webb, C.J.; Simpson, M.J.A. 2011: Seeds of New Zealand Gymnosperms and Dicotyledons. Christchurch, Manuka Press.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Epilobium chionanthum Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/epilobium-chionanthum/ (Date website was queried)