Piper excelsum subsp. psittacorum
Common names
kawakawa, pepper tree
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Trees & Shrubs - Dicotyledons
Simplified description
Fleshy shrub with jointed green twigs bearing large green glossy heart-shaped thin leaves with hard green flower spikes to 200mm long inhabiting the Kermadec Island. Leaves to 200mm wide, veins radiating from stalk, slightly peppery to taste. Fruit orange.
Detailed description
Dioecious shrub to small suckering tree up to 3 m tall, branching from base. Branches terete up to 40 mm diameter, initially bright green, maturing dull greenish-brown. Leaves mildly aromatic with a slight peppery taste when chewed; petioles u-shaped in cross-section, upper surface grooved, 20-80 mm long, green to yellow-green; lamina slightly bullate, 50-180 × 60-200 mm, pale green to dark green, rarely yellow-green, broadly ovate to suborbicular, base cordate, rounded or rarely with ends overlapping, apex distinctly acuminate, margins entire; main nerves 5-9, raised slightly above lamina surface. Inflorescence a solitary or paired spike bearing numerous, crowded flowers on a slender rachis, each flower subtended by a peltate scale 1.5-2.0 mm diameter; male spikes to 200 mm long, often faintly tapered, stamens 2-3; female spikes 40-80 mm long, style 3-4, minute; ovary ovoid. Fruiting spike 12-20 mm diameter, yellow or orange when ripe. Fruit fleshy, sweet, coalescent, with dimpled apex. Seeds 1.8-2.0 mm long, ellipsoid, grooved with 3-4 furrows, hard, peppery when crushed.
Similar taxa
Macropiper excelsum subsp. psittacorum is only known in the New Zealand Botanical Region from Raoul Island (and Norfolk Island if one wishes to include it in the New Zealand Botanical region). On either island it is the only representative of the genus present so it could not be confused with anything else. However, this subspecies is very rarely cultivated in New Zealand and so could be confused in the garden with other members of the Macropiper excelsum complex. From all of these it differs by its very thin, membranous, bullate leaves which are weakly aromatic and have almost no discernible peppery taste. It also differs by the male spikes which are the longest of the M. excelsum complex, very narrow and finely tapered. The name M. excelsum subsp. psittacorum is still widely, though incorrectly applied by many horticulturists to M. excelsum subsp. peltatum f. peltatum and sometimes even M. excelsum subsp. excelsum (see Taxonomic Notes below).
Distribution
Indigenous. Kermadec Islands (Raoul Island). Also Norfolk and Lord Howe Islands.
Habitat
Coastal forest where it is often an important component of the shrub layer.
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: OL, SO
Threats
Not Threatened. Listed because in New Zealand it is only known from Raoul Island, where it is abundant.
Detailed taxonomy
Family
Piperaceae
Synonyms
Macropiper psittacorum (Endl.) Miq.; Macropiper excelsum f. psittacorum (Endl.) A.C.Smith, Piper psittacorum Endl., Piper excelsum var. majus Cheeseman, Macropiper excelsum var. majus (Cheeseman) Allan
Taxonomic notes
The generic distinction between Macropiper and Piper has always been tenuous. Recently Jaramillo et al. (2008) have shown that Macropiper should be merged in Piper. However, they did not effect the full transfer of the New Zealand taxa to Piper. This action was taken by de Lange (2012) for Macropiper excelsum subsp. psittacorum, Macropiper excelsum subsp. peltatum f. peltatum and f. delangei.
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
August - November
Fruiting
Throughout the year
Propagation technique
Easily grown from semi-hardwood cuttings and fresh seed. Rather cold sensitive (even in Auckland). An attractive plant, well worth the effort of cultivating. It does best in semi-shade in a free draining but moist soil. Once established can tolerate considerable drought.
Other information
Etymology
piper: Pepper
excelsum: Tall
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.
PIPESS
Chromosome number
2n = 26
Previous conservation statuses
2017 | At Risk – Naturally Uncommon | Qualifiers: OL, SO
2012 | At Risk – Naturally Uncommon | Qualifiers: OL, SO
2009 | At Risk – Naturally Uncommon | Qualifiers: SO, OL
2004 | Range Restricted
Referencing and citations
References and further reading
de Lange, P.J. 2012: Taxonomic notes on the New Zealand flora: new names in Piper (Piperaceae). New Zealand Journal of Botany DOI:10.1080/0028825X.2012.708904
Jaramillo, M.A.; Callejas, R; Davidson, C.; Smith, J.F.; Stevens, A.C.; Tepe, E.J. 2008: A phylogeny of the tropical genus Piper using ITS and the chloroplast intron psbJ-petA. Systematic Botany 33: 647-660.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange 30 August 2005. Description based on live plants (wild and cultivated) and herbarium specimens.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Piper excelsum subsp. psittacorum Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/piper-excelsum-subsp-psittacorum/ (Date website was queried)