Species
+

Alectryon excelsus Gaertn.

Three Kings Titoki, titoki

Climate known 60 photographs
Add one to my plants Sow seed

Every figure on this page is derived from public data by a stated rule and says its source; nothing here is written by a person or a model, except the Wikipedia passage, which is quoted and marked as such. How it is made.

Summary

Alectryon excelsus, commonly known as tītoki, New Zealand ash, or the New Zealand oak, is a species of tree in the family Sapindaceae. It reaches 20 metres in height. It is endemic to New Zealand; its range mainly covers the North Island, but is also present in the South Island with the Banks Peninsula being its southern limit. There are two recognised subspecies of this plant: A. excelsus subsp. excelsus native to mainland New Zealand, and subsp. grandis native to the Manawatāwhi / Three Kings Islands. More on Wikipedia ›

The opening of Wikipedia, “Alectryon excelsus”, CC BY-SA 4.0, quoted as written. Kept separate from everything derived here.

Family
Sapindaceae
Described by
Gaertn.
Native to
New Zealand North, New Zealand South
Wild records
1676 in range· 538 open

At a glance

Warmest month
21°C
Feb, mean day; nights 14 °C (CHELSA)
Rain
1400mm/yr
12 wet months · peak Jul 156 mm (CHELSA)
Light
11–43DLI
mol/m²/day, winter to summer, open sky (CHELSA shortwave)
In short condensed by rule from the cultivation cards · not written by a person
Rain rule: no season, 70% of the rain takes 8 months (October to April and June in the northern hemisphere). Habitat rain 1400 mm a year, wettest July at 156 mm, driest January at 88 mm (habitat calendar, southern hemisphere). Open sky over the habitat: 11 to 43 mol/m²/day. Cold floor 3.8 °C (1st-percentile habitat night, NASA POWER).
Each sentence is one card's own one-line form, written by the same rule as the card (Its year, Rain, Light, Temperature); the note cannot say what a card does not. Months are given for the northern hemisphere (set your site in Settings to change this), and the habitat's own alongside. The cards · the figures.

Cultivation

Its year Rain rule: no season, 70% of the rain takes 8 months (October to April and June in the northern hemisphere).

This species’ habitat figures, and what two fixed rules read from them.

The rain rule reads no season: 70% of the year's rain (1020 mm of 1400 mm) takes 8 months, April to October and December. Mean temperature moves 8.6 °C between the warmest and coldest month. Months are the habitat's, southern hemisphere; shifted six months for a northern-hemisphere collection: October to April and June.

Read from the median year of CHELSA monthly rainfall and mean temperature across the envelope cells: the rain rule takes the smallest set of months carrying 70% of the rain and calls it winter when its mean is more than half a degree below the year's, summer when more than that above, and neither in between; the temperature rule, used only under 120 mm, names the cooler six months when they are at least a degree cooler than the other six. Months are shifted for the other hemisphere only where the temperature curve gives a season to reverse. A reading of the curves, not an observation of the plant.

Rain Habitat rain 1400 mm a year, wettest July at 156 mm, driest January at 88 mm (habitat calendar, southern hemisphere).

This species’ habitat figures, with their source.

1400 mm a year at the habitat, 1020 mm of it April to October and December. Wettest month July at 156 mm, driest January at 88 mm. Across the envelope cells the year's total runs 1035 mm to 1892 mm (10th to 90th percentile of each cell's own year) (median year across the envelope cells, CHELSA; habitat calendar, southern hemisphere).

CHELSA monthly precipitation, median year across the envelope cells. The rain that falls where the species is recorded; nothing about how the plant takes water.

Light Open sky over the habitat: 11 to 43 mol/m²/day.

This species’ habitat figures, with their source.

Open sky over the habitat: 11 to 43 mol/m²/day across the year (daily light integral, median year across the envelope cells, CHELSA; the lowest 10th-percentile month across the cells is 10, the highest 90th-percentile month 45).

CHELSA shortwave radiation at each envelope cell, a daily-mean flux taken to a daily total and converted at 2.07 mol of PAR per MJ. The sky over the habitat, measured; what reaches a plant under a rock, a shrub or a shade cloth is not.

Warmth and air Cold floor 3.8 °C (1st-percentile habitat night, NASA POWER).

This species’ habitat figures, with their source.

Temperature

Coldest: the 1st-percentile night over 44 years at the typical cell is 3.8 °C, the absolute minimum 1.6 °C, no frost in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 20.1 °C. Monthly means: coldest night 5.9 °C in July (across the envelope cells 3.0 °C to 10.1 °C), warmest day 20.9 °C in February (median year across the envelope cells, CHELSA). Cold floor: 3.8 °C, which is the 1st-percentile night over 44 years at the typical cell (NASA POWER).

NASA POWER daily minima and maxima 1981–2024 at the typical cell, lapse-corrected to its elevation; CHELSA monthly means, median year across the envelope cells, CHELSA. The cold floor is the figure named in its sentence. Not a measured survival limit for any plant in a pot.

Humidity

Relative humidity at the habitat: 62 to 64% across the year (monthly means, median year across the envelope cells, CHELSA). A figure about the air, saying nothing about how the plant takes water.

CHELSA relative humidity, median year across the envelope cells.

The figures the cards read from are in Climate below, and where they came from in Natural habitat.

Climate across the habitat

Habitat climate through the yearMean day from 11 °C in Jul to 21 °C in Feb; mean night from 6 °C in Jul to 14 °C in Feb. The cold quarter, Jun to Aug, is the three months around the coldest night. 1400 mm of rain a year, most in Jul. The bands show the 10th to 90th percentile across 744 habitat cells. Over 44 years at the typical cell the absolute minimum was 1.6 °C and the 99th-percentile day 20.1 °C; neither is dated to a month. Beneath: daily light integral and relative humidity through the year, each on its own scale.10°15°20°25°20.1° 99th-percentile day (undated)1.6° lowest night in 44 yrs (undated)°C · day and nightcold quarter050100150200250mm rainDLI 11–43RH 62–64 %JanFebMarAprMayJunJulAugSepOctNovDec
day night rain 10th–90th percentile across 744 habitat cells cold quarter: the three months around the coldest night extremes over 44 years at the typical cell, marked at the edge: undated DLI, mol/m²/dayRH %each on its own scale
Figures by month
JanFebMarAprMayJunJulAugSepOctNovDec
Day °C21 / 18–2221 / 18–2319 / 17–2117 / 15–1914 / 12–1712 / 10–1511 / 9–1412 / 10–1414 / 12–1515 / 13–1717 / 15–1819 / 17–21
Night °C14 / 12–1714 / 12–1813 / 10–1611 / 8–159 / 6–137 / 4–116 / 3–106 / 3–108 / 5–119 / 7–1211 / 8–1413 / 10–16
Rain mm88 / 62–12089 / 68–124100 / 77–135107 / 77–155124 / 91–165146 / 105–198156 / 113–208138 / 101–188120 / 77–172120 / 84–172103 / 73–144109 / 69–161
DLI43 / 40–4537 / 34–3929 / 28–3121 / 19–2214 / 13–1611 / 10–1313 / 11–1418 / 16–2025 / 23–2733 / 30–3540 / 36–4242 / 39–45
RH %62 / 59–6562 / 60–6562 / 60–6563 / 61–6664 / 61–6764 / 61–6864 / 62–6864 / 61–6764 / 61–6663 / 60–6662 / 59–6563 / 60–66

Each figure is the median across the 744 grid cells holding the 1660 in-range records, with the 10th–90th percentile span across those cells after the slash where it differs. Extremes and elevation were read at the typical cell 2627:7099 (-41.375, 174.975). Over 44 years there: absolute minimum 1.6 °C, 1st-percentile night 3.8 °C, 99th-percentile day 20.1 °C. Normals: CHELSA V2.1 1981–2010 climatology, 0.05° cells (each the mean of ~36 1 km pixels). Envelope: median and 10th–90th percentile of each month across the 744 distinct grid cells holding the 1660 in-range records; extremes and elevation at the typical cell 2627:7099 (its coldest month's mean night nearest the median across cells); its position is the cell centre. Extremes: NASA POWER (MERRA-2) daily 1981–2024, cell -41.50_175.000, lapse-corrected +351 m at 6.5 °C/km. Elevation: ETOPO 2022, 422 m (cell mean).

Natural habitat

Native range as published by WCVP; the marker is where the records are densest and decides nothing: the climate was read across every in-range record's cell, not at the marker.
Openly licensed records inside the range, framed on where they fall.
NativeNew Zealand North, New Zealand South
Kew's description“tree” · “subtropical”· quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Map marker-41.174, 174.817 · in the densest population, 1371 records (82% of those in range)
Evidence usedThe map marker and the climate envelope rest on all 1676 georeferenced records inside the native range; the map shows only the 538 openly licensed ones, which alone would put the marker 44 km away. 7 records outside the range (gardens, roadsides, misidentifications) ignored. 16 in-range records are placed to worse than 10 km and stay on the map but off the climate.
The map markerthe map marker: the openly licensed record nearest the middle of the densest 1° population inside the densest 2° block of the 1676 in-range records; it decides nothing.

Photographs

Alectryon excelsusAlectryon excelsusAlectryon excelsusAlectryon excelsusAlectryon excelsusAlectryon excelsusAlectryon excelsusAlectryon excelsus

Photographs: (c) Jon Sullivan, some rights reserved (CC BY); (c) Duncan Cunningham, some rights reserved (CC BY) (4); (c) Oscar Dove, some rights reserved (CC BY) (3).

Photographs: iNaturalist and Wikimedia Commons did not answer when this page was built; what is shown came from the sources that did.

Papers naming this species

Works whose title or abstract names Alectryon excelsus, most cited first, from OpenAlex (CC0). A mention, not a cultivation source: nothing on this page is drawn from them.

Endemism, species selection and the origin and distribution of the vascular plant flora of New Zealand
Matt S. McGlone, Richard P. Duncan, Peter B. Heenan (2001) · Journal of Biogeography
A quantitative assessment of shoot flammability for 60 tree and shrub species supports rankings based on expert opinion
Sarah V. Wyse, George L. W. Perry, Dean M. O’Connell, Phillip S. Holland (2016) · International Journal of Wildland Fire
Late Holocene forest disturbance in Gisborne, New Zealand: A comparison of terrestrial and marine pollen records
Janet M. Wilmshurst, Dennis N. Eden, P. C. Froggatt (1999) · New Zealand Journal of Botany
Quaternary fossil faunas from caves in Takaka Valley and on Takaka Hill, northwest Nelson, South Island, New Zealand
Trevor H. Worthy, Richard N. Holdaway (1994) · Journal of the Royal Society of New Zealand
Tree species flammability based on plant traits: A synthesis
Zorica Popović, Srdjan Bojović, Milena Marković, Artemi Cerdà (2021) · The Science of The Total Environment
A late Holocene history of natural disturbance in lowland podocarp/hardwood forest, Hawke's Bay, New Zealand
Janet M. Wilmshurst, Matt S. McGlone, T. R. Partridge (1997) · New Zealand Journal of Botany
Is dispersal easier than pollination? Two tests in New Zealand Loranthaceae
Dave Kelly, Jenny J. Ladley, Alastair W. Robertson (2004) · New Zealand Journal of Botany
Threatened and uncommon plants of New Zealand
Peter J. de Lange, Peter B. Heenan, David R. Given, David A. Norton (1999) · New Zealand Journal of Botany
Secondary forest succession differs through naturalised gorse and native kānuka near Wellington and Nelson
Jon J. Sullivan, Peter A. Williams, S. M. Timmins (2007) · Lincoln University Research Archive (Lincoln University)

Similar habitat climate the 6 species whose habitat climate is nearest this one's: mean day and night, month by month, and rain on a log scale, in calendar order, so a habitat with the same seasons six months out is far, not near. Nothing else counts: not range, not family.

History & registers

Where this page came from built 2026-09-20 · dossier v2 · node
gbif.species answeredcarried from build of 2026-09-20 (offline re-derivation; the backbone was not asked)
gbif.synonyms answeredcarried from build of 2026-09-20 (offline re-derivation; the backbone was not asked)
gbif.vernacular answeredcarried from build of 2026-09-20 (offline re-derivation; the backbone was not asked)
wcvp.distribution answered
gbif.occurrences answeredGBIF occurrence download https://doi.org/10.15468/dl.3h4zam
climate answered
wikidata answeredcarried from build of 2026-09-20 (rederive); that build: carried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
wikipedia answeredcarried from build of 2026-09-20; this build: skipped
inat.taxon not askedcarried from build of 2026-09-20 (rederive)
inat.photos.wild answeredcarried from build of 2026-09-20; this build: skipped
inat.photos.cultivated nothing to reportcarried from build of 2026-09-20 (rederive); that build: carried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
commons not askedcarried from build of 2026-09-20 (rederive); that build: carried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
gbif.media answered
openalex answeredcarried from build of 2026-09-20; this build: skipped

Every upstream is recorded as having answered, reported nothing, or refused. Only “nothing to report” is ever shown as an absence. Records came from 26 datasets via GBIF.org; each carries its own licence.