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An example collection, so you can see what this page does. Nothing added here is kept: leaving deletes it.
Isopogon trilobus; photograph (c) James (Jim) Duggan, some rights reserved (CC BY-SA) CC BY-SA(c) James (Jim) Duggan, some rights reserved (CC BY-SA) · observed growing wild · 2018-10-24

Isopogon trilobus R.Br.

Proteaceae · Western Australia

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Isopogon trilobus, photograph (c) Tyler Anthony, some rights reserved (CC BY)Isopogon trilobus, photograph (c) Tyler Anthony, some rights reserved (CC BY)Isopogon trilobus, photograph (c) Tyler Anthony, some rights reserved (CC BY)Isopogon trilobus, photograph (c) Em Lamond, some rights reserved (CC BY)Isopogon trilobus, photograph (c) Tyler Anthony, some rights reserved (CC BY)Isopogon trilobus, photograph (c) Tyler Anthony, some rights reserved (CC BY) 61 photographs ›
Habitat figures
Cold floor (1 night in 100)
4.1°C
Record low 1.5 °C in 44 years, at a typical spot in the range NASA POWER
Warmest month, mean daily high
25°C
Jan and Feb at the habitat CHELSA
Rain a year (median across the range)
493mm
10 months of 25 mm or more in the median year CHELSA
Open-sky light
15–47DLI
Lowest to highest month (DLI) CHELSA
The year in your months, northern hemisphere
  1. Jan
  2. Feb
  3. Mar
  4. Apr
  5. May
  6. Jun
  7. Jul
  8. Aug
  9. Sep
  10. Oct
  11. Nov
  12. Dec
Wet winters: the rain comes October to April (April to October at the habitat), read as a winter growing season. rain rule, CHELSA
Northern hemisphere unless you set your site. The chart is in the habitat's months.

Summary

Isopogon trilobus, commonly known as barrel coneflower, is a species of flowering plant in the family Proteaceae and is endemic to South Coast Western Australia. It is a shrub with wedge-shaped leaves with lobed or toothed margins, and oval, spherical or barrel-shaped heads of cream-coloured to yellow flowers.

Quoted from Wikipedia, "Isopogon trilobus", CC BY-SA 4.0.

Cultivation

Seasons

The rain rule reads a winter growing season: 70% of the median year's rain (352 mm of 495 mm) falls in April to October, cooler than the year (wet-season mean 13.9 °C against a yearly mean of 15.9 °C). Months are the habitat's, southern hemisphere; shifted six months for a northern-hemisphere collection: October to April.

Rain

495 mm in the median year at the habitat, 352 mm of it April to October. Wettest month July at 61 mm, driest month February at 21 mm. Across the grid cells of the range the year's total runs 419 mm to 617 mm, the 10th to 90th percentile of each cell's own year. The median of the cells' own yearly totals, 493 mm, is the year's rain at the top of the page; the 495 mm here is the median year's, the twelve monthly medians added, which the rain rule reads. Habitat calendar, southern hemisphere; median year across the grid cells of the range, CHELSA.

Light

Open sky over the habitat: 15 to 47 mol/m²/day across the year (daily light integral, median year across the grid cells of the range, CHELSA; the lowest 10th-percentile month across the cells is 14, the highest 90th-percentile month 47).

Warmth and air
Temperature

Coldest: the 1st-percentile night over 44 years at a typical spot in the range is 4.1 °C, the absolute minimum 1.5 °C, no frost in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 38.3 °C. Monthly means: the coldest month's mean nightly low 8.4 °C in July and August (across the grid cells of the range 6.1 °C to 10.6 °C), the warmest month's mean daily high 25.2 °C in February (median year across the grid cells of the range, CHELSA). Cold floor: 4.1 °C, which is the 1st-percentile night over 44 years at a typical spot in the range (NASA POWER).

Humidity

Relative humidity at the habitat: 57 to 58% across the year (monthly means, median year across the grid cells of the range, CHELSA). A figure about the air, saying nothing about how the plant takes water.

How this section is made

Each card states this species' habitat figures with their sources, and what two fixed rules read from them; nothing here says what the plant does, wants or tolerates. The rules · the terms.

Seasons. Read from the median year of CHELSA monthly rainfall and mean temperature across the grid cells of the range: 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 moves 4 °C or more and the habitat lies 10° or more from the equator. A reading of the curves, not an observation of the plant.

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

Light. 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.

Temperature. NASA POWER daily minima and maxima over 44 years at a typical spot in the range, lapse-corrected -6 m to its elevation; CHELSA monthly means, median year across the grid cells of the range. The cold floor is the 1st-percentile night named in its sentence. Not a measured survival limit for any plant in a pot.

Humidity. CHELSA relative humidity, median year across the grid cells of the range.

Climate across the habitat

Habitat months, southern hemisphere

Habitat climate of Isopogon trilobus through the yearWarmest months January and February, mean daily high 25 °C; coldest months July and August, mean nightly low 8.4 °C; 495 mm of rain in the median year (the twelve monthly medians added). Medians across the range, from CHELSA; the extremes at the edge from NASA POWER. Habitat months, southern hemisphere.0°10°20°30°40°38.3° 99th-percentile day, NASA POWER1.5° lowest night in 44 years, NASA POWER°C · day and nightcold quarter0255075100mm rainDLI 15–47RH 57–58%JanFebMarAprMayJunJulAugSepOctNovDec
day night rain medians and 10th–90th percentile across 187 habitat cells, CHELSA cold quarter: the three months around the coldest month's mean nightly low extremes over 44 years at a typical spot in the range, from NASA POWER, marked at the edge, in no month DLI, mol/m²/dayRH %each on its own scale
Figures by month
JanFebMarAprMayJunJulAugSepOctNovDec
Day °C25 / 22–2725 / 23–2724 / 22–2522 / 21–2319 / 18–1916 / 15–1715 / 14–1616 / 15–1718 / 16–1919 / 18–2122 / 20–2424 / 21–25
Night °C16 / 14–1716 / 14–1715 / 13–1713 / 11–1511 / 9–149 / 7–128 / 6–118 / 6–1110 / 7–1211 / 9–1313 / 11–1414 / 12–16
Rain mm33 / 21–3821 / 17–2533 / 29–4035 / 29–4355 / 45–7058 / 42–8361 / 46–8957 / 45–8248 / 39–6238 / 31–4634 / 30–3922 / 19–26
DLI46 / 45–4741 / 40–4233 / 31–3424 / 23–2518 / 17–1815 / 14–1616 / 15–1621 / 20–2128 / 26–2937 / 34–3843 / 41–4447 / 45–47
RH %58 / 56–5958 / 56–5958 / 57–5958 / 57–5958 / 57–6058 / 57–6158 / 57–6157 / 56–6157 / 56–6057 / 56–5957 / 56–5957 / 56–59
How this section is made
Each figure is the median across the 187 grid cells on land that hold in-range records (323 records in those cells; 1 more cell holds records but no land by the elevation layer, so those records sit at sea and the cell is left out), with the 10th–90th percentile span across those cells after the slash where it differs. A dash is a month one or more of those cells has no figure for in the grid (a variable CHELSA does not carry there), so no median is taken rather than one over fewer cells. Extremes and elevation were read at a typical spot in the range, cell 2478:5989 (-33.925, 119.475). Over 44 years there: absolute minimum 1.5 °C, 1st-percentile night 4.1 °C, 99th-percentile day 38.3 °C. Normals: CHELSA V2.1 1981–2010 climatology, 0.05° cells (each the mean of ~36 1 km pixels). Across the range: median and 10th–90th percentile of each month across the 187 distinct grid cells holding 323 of the 324 in-range records (1 further cell with records at sea, by the elevation layer, left out); extremes and elevation at the typical cell 2478:5989 (its coldest month's mean nightly low nearest the median across cells); its position is the cell centre. Extremes: NASA POWER (MERRA-2) daily 1981–2024, cell -34.00_119.375, lapse-corrected -6 m at 6.5 °C/km. Elevation: ETOPO 2022, 161 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 the cells of the in-range records placed well enough to read one, not at the marker.
Openly licensed records inside the range, framed on where they fall.
NativeWestern Australia · regions are the level-3 units of the World Geographical Scheme for Recording Plant Distributions, as Kew's World Checklist records ranges, some under historical names such as Yugoslavia or Czechoslovakia (how).
Map marker-33.94, 119.579 · in the densest population, 263 records (68% of those in range)
Kew's description“shrub” · quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Evidence usedThe map marker rests on all 388 georeferenced records inside the native range; the climate across the range on the 323 of them in the land cells it reads, of 324 placed to within 10 km; the map shows only the 255 openly licensed ones, which alone would put the marker 1 km away. 64 in-range records are placed to worse than 10 km, or with no stated accuracy (admitted only as a person's observation to three decimals), and stay on the map but off the climate.
How this section is made
The map marker: the openly licensed record nearest the middle of the densest 1° population of the 388 in-range records; it decides nothing. Records outside the native range, living specimens and records marked introduced are not used; which records count.

Photographs

Isopogon trilobus, photograph 1did not loadIsopogon trilobus, photograph 2did not loadIsopogon trilobus, photograph 3did not loadIsopogon trilobus, photograph 4did not loadIsopogon trilobus, photograph 5did not loadIsopogon trilobus, photograph 6did not load

Photographs: (c) Tyler Anthony, some rights reserved (CC BY) (5); (c) Em Lamond, some rights reserved (CC BY).

Similar habitat climate The 6 nearest by mean daily high, mean nightly low and rain, month by month. How.

Anigozanthos rufus Anigozanthos rufus Red kangaroo-paw Photo: CC BY, Hugo InnesBanksia repens Banksia repens Creeping Banksia Photo: CC BY, Em LamondEucalyptus tetraptera Eucalyptus tetraptera Four-wing mallee Photo: CC0, author not statedGrevillea nudiflora Grevillea nudiflora Proteaceae Photo: CC BY, Kym NicolsonEucalyptus lehmannii Eucalyptus lehmannii Bushy yate Photo: CC BY, Em LamondEucalyptus mcquoidii Eucalyptus mcquoidii Quoin Head Marlock Photo: CC BY-SA, User:Zenwort

Other Isopogon 11 in the reference

Isopogon anemonifolius Isopogon anemonifolius Broad-leaf Drumsticks Photo: CC BY, Thomas MesaglioIsopogon anethifolius Isopogon anethifolius Narrow-leaf Drumsticks Photo: CC BY, ian_mcallanIsopogon ceratophyllus Isopogon ceratophyllus Horny Cone-Bush Photo: CC0, author not statedIsopogon cuneatus Isopogon cuneatus Proteaceae Photo: CC BY, Em LamondIsopogon dawsonii Isopogon dawsonii Nepean Conebush Photo: CC BY, ian_mcallanIsopogon divergens Isopogon divergens Spreading-coneflower Photo: CC BY, smathichongIsopogon dubius Isopogon dubius Pincushion-coneflower Photo: CC BY, Luke LythgoeIsopogon formosus Isopogon formosus Rose-coneflower Photo: CC BY, Em LamondIsopogon latifolius Isopogon latifolius Proteaceae Photo: CC0, author not statedIsopogon petiolaris Isopogon petiolaris Proteaceae Photo: CC BY, Samuel FrankelIsopogon prostratus Isopogon prostratus Proteaceae Photo: CC BY, Bryce Watts-Parker

Names & registers

Also known as Atylus trilobus; Atylus tripartitus; Isopogon trilobus var. elobata; Isopogon tripartitus; Isopogon tripartitus var. plurilobus and 2 more. (GBIF Backbone)

GBIFPOWOIPNIWikidataWikipediaiNaturalist

The record

Family
Proteaceae
Described by
R.Br.
Native to
Western Australia
Wild records
388 in range · 255 open

Every figure here is derived from public data by a stated rule and names its source; nothing about this species is written for its page by a person or by AI, apart from the marked, credited quotations. How →

Where this page came from built 2026-10-22
GBIF species record gbif.species answeredasked 2026-10-22
GBIF synonyms gbif.synonyms answeredasked 2026-10-22
GBIF common names gbif.vernacular answeredasked 2026-10-22names fetched 2026-10-22
WCVP native range wcvp.distribution answeredas of 2026-06-04
GBIF occurrence records gbif.occurrences answeredas of 2026-10-21GBIF occurrence download https://doi.org/10.15468/dl.hbdw64, of 2026-10-21; 1 record within 1 km of a botanic garden, herbarium or zoo left out (1 at a botanic garden or arboretum; Wikidata's list)
Habitat climate climate answeredasked 2026-10-22
Daily extremes (NASA POWER) climate.extremes answeredasked 2026-10-22NASA POWER (MERRA-2) daily 1981–2024, cell -34.00_119.375, lapse-corrected -6 m at 6.5 °C/km
Wikidata wikidata answeredasked 2026-10-22
Wikipedia wikipedia answeredasked 2026-10-22
iNaturalist photographs, wild inat.photos.wild answeredasked 2026-10-22from iNaturalist's open data of 2026-09-27: research-grade observations with an open-licence photograph, the 24 whose photographs iNaturalist received last (the open data holds no votes); filled 2026-10-22
iNaturalist photographs, cultivated inat.photos.cultivated not asked
GBIF media gbif.media answeredasked 2026-10-22
OpenAlex papers openalex not askednot yet asked for this reference; a later fill takes the papers from OpenAlex's snapshot

Every source is recorded as having answered, reported nothing, refused, failed, not been asked, or answered twice where one answer is taken (“not taken: two items answered”), and, for a source asked when this page was built, when: the figures are as the source held them that day; a source read from a file (Kew's World Checklist, a GBIF download) says "as of" the file's day instead; a row carried from an earlier build of the page names that build instead. Only “nothing to report” is ever shown as an absence. Records came from 18 datasets via GBIF.org; each carries its own licence.

Cultifolio

Opening your plants…