Epilobium forbesii
Common names
Forbes’s willowherb
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Flower colours
White, Yellow
Detailed description
Stout, thick almost coriaceous-leaved perennial herb of fine grained scree slopes. Plants branched from woody base. Tap root deeply descending. Leaves subsessile to sessile, crowded on 40-150 tall stems; stems brown or purple, densely glandular-pubescent and with an admixture of shorter non glandular hairs. Leaves mostly opposite, becoming alternate and crowded in the inflorescence, 6-32 x 3-13 mm, dull green to purple-green, narrowly to broadly obovate, apex obtuse to subacute, base attenuate, lamina serrated (with 6-26 teeth), lateral veins evident, 2-4 on either side of midrib. Inflorescence and flowers erect. Ovaries 4-6 mm long, green or dark green, desnely glandular-pubescent, sessile. Floral tube 2 x 2.3 mm, abaxially densely glandular-pubescent with sparse long hairs near base. Petals 7-9 x 3.6-4.4. mm, white, notch 1.5-1.7 mm deep. Anthers yellow, 0.6-0.7 x 0.5-0.6 mm; filaments of longer stamens 2.1-2.5 mm long, those of shorter 1.6-1.7 mm long; stigma 2.0 x 0.7 mm, white, clavate. Capsules subsessile, 10-18 mm long, dark brown, initially glandular-pubescent maturing glabrate. Seeds 1.8-2.0 x 0.8-0.9 mm, purplish-brown, obovoid, smooth; coma 3.6-6.5 mm long, detaching readily, typically remaining in capsule until all seed have fallen out.
Similar taxa
Distinguished from all other New Zealand Epilobia except E. astonii (Allan) Raven et Engelhorn and E. pubens A.Rich. by the leaves and inflorescences densely covered in glandular hairs. From E. astonii and E. pubens it is distinguished by the erect inflorescence and subsessile capsules. Epilobium forbesii is further distinguished by its restriction to the sparsely vegetated eastern Marlborough and north Canterbury fine-grained, alpine screes that are present only within the greywacke mountains of the dry zone east of the main divide.
Distribution
Endemic. South Island, eastern Marlborough on high greywacke mountains centred on the headwaters of the upper, Awatere, Clarence and Wairau Rivers. Also in north Canterbury (Mt Terako).
Habitat
Alpine (1300-1800 m a.s.l.). Inhabiting fine grained scree often just downslope of rock outcrops on sparsely vegetated mountains within the inner dry zone of eastern Marlborough.
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 but extremely local hence its listing as Range Restricted.
Detailed taxonomy
Family
Onagraceae
Synonyms
None
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
January - March
Fruiting
January - May
Life cycle and dispersal
Minute pappate seeds are wind dispersed (Thorsen et al., 2009).
Propagation technique
Difficult. Should not be removed from the wild
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.
EPIFOR
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 forbesii Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/epilobium-forbesii/ (Date website was queried)