Senecio esleri
Common names
Esler’s fireweed
Biostatus
Native
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 | Qualifiers: TO
Category
Vascular
Structural class
Herbs - Dicotyledonous composites
Flower colours
Yellow
Detailed description
Erect herb, usually annual, rarely a short-lived perennial, up to c. 2 m tall. Stems striate, often tinged purple, sparsely to densely setose especially above, branched above to form inflorescence. Lower cauline leaves almost glabrous to sparsely setose on upper surface, almost glabrous to moderately setose on lower especially on mid vein, apetiolate and longcuneate, 1-pinnatifid to 1/2-2/3 width, elliptic to narrow-obovate, acute at apex, c. 80-200 X 15-80 mm; segments narrow- to ovate-oblong, irregularly toothed; mid cauline leaves slightly larger, more deeply dissected with narrow-oblong toothed segments, sometimes amplexicaul and often 3-fid at base; uppermost leaves more ovate, sometimes with more or less linear segments. Capitula in loose panicles, 1-2 mm diameter. Supplementary bracts 3-10, lanceolate, ciliolate, 1-2 mm long. Involucral bracts (11>12-13, linear, usually glabrous, sometimes with a few scattered hairs, 4.5-5.5 mm long. Outer florets c. 24-35, female, filiform; inner florets c. 4-11, hermaphrodite, tubular. Achenes narrowly ellipsoid-cylindric, slightly narrowed and constricted below apex, with 2-3 rows of short antrorse hairs in grooves between or on edges of broad ribs and sometimes appearing evenly hairy, 2-2.3 mm long; pappus 5-7 mm long.
Similar taxa
Senecio bipinnatisectus but can be distinguished from that species by the setose stems, less divided lower leaves, greater number of involucral bracts, and hairier achenes. S. hispidulus var. dissectus is also similar but this is immediately distinguished by the less dissected upper cauline leaves and the densely hispid upper surface of the leaf lamina. See Thompson, I.R. 2006: A taxonomic treatment of the tribe Senecioneae (Asteraceae) in Australia. Muelleria 24: 51–110.
Distribution
Indigenous. New Zealand, North Island from Te Paki to Rotorua (see de Lange 1997, 1995; P. J. de Lange unpubl. data). Also Australia, where it is an uncommon montane species of New South Wales and Tasmania
Habitat
Waste places and coastal habitats in Northland and the Auckland area. Especially roadsides, street margins, rock walls, waste places, gardens and sand dunes.
Detailed taxonomy
Genus
Family
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
September to April
Fruiting
October to August
Propagation technique
An aggressive weedy species. Senecio esleri grows quickly and rapidly from seed and prefers sunny, disturbed sites
Other information
Extra information
Senecio esleri was first described from New Zealand by Webb (1989) who considered it to be an introduced weed (but with little elaboration as to why), probably of Australian origin. Subsequently Thompson (2004) described the same species from Australia as S. brevitubulus I.Thomps. (not realising at the time that it had already been named from New Zealand material - see Thompson 2006). de Lange & Rolfe (2010) regard Senecio esleri as a recent indigenous natural arrival to New Zealand. It was first recorded in New Zealand from a remote part of Whangaruru Harbour, Northland in 1972 and it has subsequently spread from Northland south to Taupo.
Although weedy it is difficult to understand how such an uncommon montane Australian species could have been introduced to New Zealand by human agency (deliberate or accidental). Further, its pattern of arrival and spread is identical to many other “weedy” species accepted as indigenous, e.g., Picris angustifolia, Senecio hispidulus (glabrous form). One peculiar facet of New Zealand botany is the assumption that our indigenous flora is somehow static and so anything new (i.e. indigenous) that appears (meaning that it was not recorded by botanists working in the 1800s and early 1900s) and which is shared with Australia (or the South Pacific) is automatically naturalised. Heenan & de Lange (2009) argued that for those plants found within these regions and whose seed is suited to long distance dispersal, claims of indigenous or naturalised status needs to be carefully evaluated and explained on a case by case basis.
Etymology
senecio: From the Latin senex ‘old man’ (probably referring to the bearded seeds)
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.
SENESL
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 | Qualifiers: TO
2012 | Not Threatened
2004 | Exotic
Regional conservation statuses
Auckland: 2025 | Regionally Not Threatened | Qualifiers: DPS, TO, TL
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Auckland conservation status information is sourced from the “Conservation status of vascular plant species in Tāmaki Makaurau / Auckland” Simpkins E et al. (2025) report.
Referencing and citations
References and further reading
de Lange, P.J.; Rolfe, J.R. 2010: New Zealand Indigenous Vascular plant Checklist. Wellington, New Zealand Plant Conservation Network
Heenan, P.B.; de Lange, P.J.; Keeling, J. 2009: Alternanthera nahui, a new species of Amaranthaceae indigenous to New Zealand. New Zealand Journal of Botany 47(1): 97–105.
Thompson, I.R. 2004: Taxonomic studies of Australian Senecio (Asteraceae): 1. The disciform species. Muelleria 19: 101–214.
Thompson, I.R. 2006: A taxonomic treatment of tribe Senecioneae (Asteraceae) in Australia. Muelleria 24: 65.
Webb, C.J. 1989: Senecio esleri (Asteraceae), a new fireweed. New Zealand Journal of Botany 27: 565-567.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (12 July 2005). Description based on Webb (1989)
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Senecio esleri Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/senecio-esleri/ (Date website was queried)