Epilobium wilsonii
Common names
Wilson’s willowherb
Biostatus
Native
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Flower colours
Red/Pink, White
Detailed description
Clump forming perennial herb of calcareous rocks. Branching freely from base and also above; stems 60-300 mm tall, wiry and pliant; usually purplish sometimes green with broad lines of non glandular appressed or erect hairs running down from the margins of the petioles, pubescent otherwise and this increasing and including larger numbers of glandular hairs within the inflorescence. Leaves opposite, alternate in inflorescence, coriaceous; petiole 1-3 mm long; leaf lamina 10-40 x 6-20 mm, dull grey green to green, ovate to broadly ovate, apex acute, base attentuate to rounded, margins serrulate (bearing 4-8 teeth) or entire; lateral veins obscure. Inflorescence and flowers erect to nodding. Ovaries 10-24 mm long, sparsely pubescent or covered with erect non glandular hairs, sometimes glabrous, sessile or on pedicels up to 4 mm long. Floral tube 1.8-2.5 x 2.0-3.0 mm. Sepals keeled, 5.0-10.5 x 1.5-3.0 mm, sparsely glandular-pubescent or bearing erect non-glandular hairs. Petals 10-18 x 6-15 mm, white or pink, notch 3-5 mm deep. Anthers 1.6-2.2 x 0.6-1.0 mm, yellow; filaments of the longer stamens 1.5-8.0 mm long, those of shorter 0.9-5.5 mm long. Style 4.5-14.0 mm, white; stigma 2.2-3.8 x 1.2-2.0 mm, white, capitate to short-capitate. Capsule 19-55 mm long on pedicels 7-15 mm long; surface glandular-pubescent or bearing erect non-glandular hairs, occasionally glabrous. Seeds 1.4-2.2 x 0.5-0.6 mm, brown, narrowly obovoid, finely papillose; coma 5-6 mm long, detaching readily or persistent.
Similar taxa
Distinguished from other indigenous epliobia by the thick, coriaceous, often entire, ovate leaves, wiry stems; flowers with white to pink-flushed petals, and by the sepals which are 5.0-10.5 mm long. It is one of only a few species endemic to calcareous substrates.
Distribution
Endemic. South Island, eastern Marlborough (from near Lake Grassmere to Mt Fyffe and the Kaikoura Peninsula) and north Canterbury (Waikari River, Mt Terako and Motunau Beach). Also on the Owen Range, Kahurangi National Park, north west Nelson
Habitat
Coastal to alpine (0-1200 m a.s.l.) on calcareous rocks in open shrubland, grassland or rock field
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.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – these interim threat classification statuses has not been assessed by the NZTCS panel.
- 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 | At Risk – Naturally Uncommon | Qualifiers: Sp, DPS, DPT, RR
Threats
Not threatened. Listed because it has a rather localised distribution centred on the limestone country of eastern Marlbrough and north Canterbury. However, its disjunct occurrence on the Owen massif, north west Nelson, and diffuse distribution within Marlborough and Canterbury suggests that it would be better ranked as Sparse.
Detailed taxonomy
Family
Onagraceae
Synonyms
Epilobium chlorifolium var. kaikourense Cockayne, Epilobium wilsonii var. pallidum G.Simpson et J.S.Thomson
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
November - April
Fruiting
November - June
Life cycle
Minute pappate seeds are wind dispersed (Thorsen et al., 2009).
Propagation technique
Easily grown from fresh seed and rooted pieces. Does well in a free draining soil in full sun. Inclined to become weedy.
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.
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.
EPIWIL
Chromosome number
2n = 36
Previous conservation statuses
2017 | At Risk – Naturally Uncommon | Qualifiers: DP, RR, Sp
2012 | At Risk – Naturally Uncommon | Qualifiers: RR, Sp
2009 | At Risk – Naturally Uncommon
2004 | Range Restricted
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 6 January 2008. 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 wilsonii Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/epilobium-wilsonii/ (Date website was queried)