Epilobium chlorifolium
Common names
mountain willowherb
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Flower colours
White
Detailed description
Clumped perennial herb, branched from the base and sometimes also above, the stems 70-450 mm tall; stems with strigulose lines running down from the margins of the petioles, evenly pubescent with an increasing proportion of glandular hairs in the inflorescence. Leaves opposite, alternate in the inflorescence, dill, the lateral veins prominent, 3-4 on each side of the midrib; petioles 0-2 mm long; lamina 10-30 × 12-20 mm, narrowly ovate to broadly ovate, apex acute, base rounded to obtuse, margins serrulate with 3-9 teeth on each side. Flowers erect. Ovaries 10-18 mm long, densely glandular-pubescent, some with with a few strigulose hairs; on a pedicel 1-3 mm long. Floral tube 0.9-1.4 × 1.2-2.4 mm. Sepals 3.0-5.6 × 1.2-1.5 mm, keeled, sparsely glandular-pubescent, often abaxially strigulose. Petals 7-11 × 5-8 mm, notch 1.2-1.6 mm deep, white. Stamen filaments white of two types: long (2.2-4.5 mm long) and short (1.4-2.5 mm long), Anthers 1.0-1.7 × 0.4-1.0 mm, yellow. Style 3.3-5.2 mm long, white; stigma 1.2-2.2 x 0.5-0.8 mm, white, clavate, surrounded by the anthers at anthesis or held well above them. Capsule 39-52 mm long, glandular-pubescent, sometimes with a few strigulose hairs, on a pedicel 15-25 mm long. Seeds 1.3-1.7 mm long, brown, obovate, sometimes with a narrow truncated beak, base subacute, finely reticulate-mammillate; coma 5-11 mm long, white, caducous.
Similar taxa
Allied to basicolous Epilobium wilsonii with which it shares amolnst other characters pubescent ovaries whose indumentum is comprised solely of erect, glandular hairs. However, it differs from this narrow-range Kaikoura Coastline - South Marlborough endemic, by the much wider and less ecologically confined distribution; by the sepals which are 2.0-5.6 mm rather than 5.0-10.5 mm long in E. wilsonii; by the smaller petals (7-11 mm long cf. 10-18 mm long in E. wilsonii), and mostly smaller seeds 1.3-1.7 mm cf. 1.4-2.2 mm long) and distinctly longer coma (5-11 mm cf. 5-8 mm long in E. wilsonii).
Distribution
Endemic. New Zealand: North and South Islands from Mt Hikurangi, the main axial ranges, Mt Taranaki and the Central Volcanic Plateau south.
Habitat
Subalpine to Alpine. Mostly in tussock grassland and herbfield but extending into the bushline along stream sides. Epilobium chlorifolium has also been collected once, as a weed of gravel ballast in a railway shunting yard.
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | Not Threatened
Detailed taxonomy
Family
Synonyms
Epilobium chloraefolium
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
October - April
Fruiting
October - July
Life cycle and dispersal
Minute pappate seeds are wind dispersed (Thorsen et al., 2009).
Propagation technique
Easily grown from fresh seed and rooted pieces. Does best in a rockery. Dislikes warm, humid climates where it is prone to getting powdery mildew.
Other information
Where To Buy
Not commercially available.
Etymology
epilobium: From the Greek epi- ‘upon’ and lobos ‘a pod’, the flowers appearing to be growing on the seed pod.
chlorifolium: Green leaved
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.
EPICHL
Chromosome number
2n = 36
Previous conservation statuses
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Not Threatened
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Regional conservation statuses
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Otago conservation status information is sourced from the “Regional conservation status of indigenous vascular plants in Otago” Jarvie S et al. (2024) report.
Otago: 2024 | Regionally Not Threatened
Referencing and citations
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.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (1 September 2011) Description adapted from Raven & Raven (1976) and Webb & Simpson (2001)
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Epilobium chlorifolium Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/epilobium-chlorifolium/ (Date website was queried)