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Erythronium montanum; photograph (c) bloodshot20, some rights reserved (CC BY) CC BY(c) bloodshot20, some rights reserved (CC BY) · observed growing wild · 2026-06-24

Erythronium montanum S.Watson

White avalanche lily; White glacier lily; Avalanche lily; Glacier fawn lily

Liliaceae · British Columbia, Oregon +1 · listed by its family as a bulb, tuber or caudex

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Erythronium montanum, photograph (c) Tom and T Herman, some rights reserved (CC BY)Erythronium montanum, photograph (c) Tom and T Herman, some rights reserved (CC BY)Erythronium montanum, photograph (c) Josie Graydon, some rights reserved (CC BY)Erythronium montanum, photograph author not stated, no rights reservedErythronium montanum, photograph author not stated, no rights reservedErythronium montanum, photograph author not stated, no rights reserved 66 photographs ›
Habitat figures
Cold floor (1 night in 100)
-12.6°C
Record low -22.9 °C in 44 years, at a typical spot in the range NASA POWER
Warmest month, mean daily high
20°C
Jul and Aug at the habitat CHELSA
Rain a year (median across the range)
2,856mm
12 months of 25 mm or more in the median year CHELSA
Open-sky light
6–43DLI
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 March, with nights below freezing; no growing season read. rain rule, CHELSA
Northern hemisphere unless you set your site. The chart is in the habitat's months.

Summary

Erythronium montanum, the avalanche lily or white avalanche lily, is a member of the lily family native to coastal British Columbia and the alpine and subalpine Olympic and Cascade Ranges of the Pacific Northwest of Washington and Oregon.

Quoted from Wikipedia, "Erythronium montanum", CC BY-SA 4.0.

About the genus · Erythronium

Erythronium, the fawn lily, trout lily, dog's-tooth-violet or adder's tongue, is a genus of Eurasian and North American plants in the lily family, most closely related to tulips. The name Erythronium derives from Ancient Greek ἐρυθρός (eruthrós) "red" in Greek, referring to the red flowers of E. dens-canis. Of all the established species, most live in North America; only seven species are found in Europe and Asia.

Quoted from Wikipedia, "Erythronium", CC BY-SA 4.0.

Cultivation

Grouped as a bulb, tuber or caudex, listed under the family Liliaceae in the archetype table, and Kew describes it as “bulbous geophyte”.

Seasons

The rain rule reads a rainy season and no growing season: 70% of the median year's rain (2,117 mm of 2,768 mm) falls in October to March, the cooler part of the year, but the mean nightly low is below freezing in February, March, April, December and January, so the rule reads no growing season from it. Months are the habitat's, northern hemisphere; shifted six months for a southern-hemisphere collection: April to September.

Rain

2,768 mm in the median year at the habitat, 2,117 mm of it October to March. Wettest month November at 454 mm, driest month July at 43 mm. Across the grid cells of the range the year's total runs 1,906 mm to 3,816 mm, the 10th to 90th percentile of each cell's own year. The median of the cells' own yearly totals, 2,856 mm, is the year's rain at the top of the page; the 2,768 mm here is the median year's, the twelve monthly medians added, which the rain rule reads. Habitat calendar, northern hemisphere; median year across the grid cells of the range, CHELSA.

Light

Open sky over the habitat: 6 to 43 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 5, 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 -12.6 °C, the absolute minimum -22.9 °C, 8,977 frost nights in 44 years, 204.0 a year (NASA POWER daily minima). Warmest: the 99th-percentile day is 22.8 °C. Monthly means: the coldest month's mean nightly low -5.0 °C in December (across the grid cells of the range -8.1 °C to -1.5 °C), the warmest month's mean daily high 20.1 °C in August (median year across the grid cells of the range, CHELSA). Cold floor: -12.6 °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 66% 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 +860 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.

Group. Listed under the family Liliaceae in the archetype table, and Kew describes it as “bulbous geophyte”. A group is taken only where Kew's description of the species agrees with the table's listing. The table gives no figure and no prose; the cold floor is the habitat's alone.

Climate across the habitat

Habitat months, northern hemisphere

Habitat climate of Erythronium montanum through the yearWarmest months July and August, mean daily high 20 °C; coldest month December, mean nightly low -5.0 °C; 2,768 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, northern hemisphere.-30°-20°-10°0°10°20°30°frost22.8° 99th-percentile day, NASA POWER-22.9° lowest night in 44 years, NASA POWER°C · day and nightcold quarter0200400600800mm rainDLI 6–43RH 57–66%JanFebMarAprMayJunJulAugSepOctNovDec
day night rain medians and 10th–90th percentile across 206 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 °C1 / -2–42 / -1–54 / 1–77 / 4–1011 / 8–1415 / 12–1820 / 16–2320 / 16–2317 / 14–2010 / 7–134 / 1–60 / -3–3
Night °C-4 / -7–-1-5 / -7–-1-4 / -6–0-2 / -5–11 / -2–55 / 2–88 / 5–108 / 6–116 / 3–92 / -1–5-3 / -6–1-5 / -8–-2
Rain mm407 / 289–587293 / 204–402290 / 184–395204 / 128–266143 / 96–189111 / 72–15343 / 26–7248 / 32–80102 / 64–144254 / 170–370454 / 329–626419 / 301–604
DLI8 / 6–914 / 12–1621 / 19–2329 / 28–3235 / 34–3839 / 37–4243 / 41–4738 / 36–4229 / 26–3116 / 14–198 / 7–106 / 5–8
RH %65 / 61–6863 / 59–6564 / 62–6663 / 61–6462 / 60–6362 / 59–6358 / 54–6057 / 54–5957 / 54–5961 / 58–6366 / 62–6964 / 60–67
How this section is made
Each figure is the median across the 206 grid cells holding the 1095 in-range records, 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 841:1131 (47.925, -123.425). Over 44 years there: absolute minimum -22.9 °C, 1st-percentile night -12.6 °C, 99th-percentile day 22.8 °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 206 distinct grid cells holding 1095 of the 1095 in-range records; extremes and elevation at the typical cell 841:1131 (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 48.00_-123.125, lapse-corrected +860 m at 6.5 °C/km. Elevation: ETOPO 2022, 1337 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.
NativeBritish Columbia, Oregon, Washington · 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 marker46.79, -121.783 · in the densest population, 1109 records (90% of those in range)
Kew's description“bulbous geophyte” · “temperate” · quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Evidence usedThe map marker rests on all 1228 georeferenced records inside the native range; the climate across the range on the 1095 of them placed to within 10 km; the map shows only the 299 openly licensed ones, which alone would put the marker 2 km away. 1 record outside the WCVP native range not used. 133 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 1228 in-range records; it decides nothing. Records outside the native range, living specimens and records marked introduced are not used; which records count.

Photographs

Erythronium montanum, photograph 1did not loadErythronium montanum, photograph 2did not loadErythronium montanum, photograph 3did not loadErythronium montanum, photograph 4did not loadErythronium montanum, photograph 5did not loadErythronium montanum, photograph 6did not load

Photographs: (c) Tom and T Herman, some rights reserved (CC BY) (2); (c) Josie Graydon, some rights reserved (CC BY); author not stated, no rights reserved · CC0 (3).

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

Androsace laevigata Androsace laevigata Cliff Douglasia Photo: CC BY, John BrewAbies amabilis Abies amabilis Pacific silver fir Photo: CC0, author not statedLomatium martindalei Lomatium martindalei Cascade desert-parsley Photo: CC BY, J StrakaCaltha biflora Caltha biflora Broad-leaved marsh marigold Photo: CC0, author not statedCarex mertensii Carex mertensii Mertens' sedge Photo: CC0, author not statedMicranthes ferruginea Micranthes ferruginea Rusty saxifrage Photo: CC BY-SA, Nick T.

Other Erythronium 28 in the reference

Erythronium albidum Erythronium albidum White trout lily Photo: CC0, author not statedErythronium americanum Erythronium americanum Yellow adder's-tongue Photo: CC BY, Patrick JacksonErythronium californicum Erythronium californicum California fawn-lily Photo: CC BY, gretchenparadisErythronium caucasicum Erythronium caucasicum Caucasian Dog's Tooth Violet Photo: CC BY, Виктория БилоусErythronium citrinum Erythronium citrinum Cream Fawn Lily Photo: CC BY, Dee Shea HimesErythronium dens-canis Erythronium dens-canis Dog's-tooth-violet Photo: CC BY, Barry StewartErythronium elegans Erythronium elegans Coast Range Fawn-lily Photo: CC BY, Dee Shea HimesErythronium grandiflorum Erythronium grandiflorum Glacier lily Photo: CC BY, Cody HinchliffErythronium helenae Erythronium helenae Pacific fawnlily Photo: CC BY, Ken-ichi UedaErythronium hendersonii Erythronium hendersonii Henderson's fawn-lily Photo: CC BY, Dee Shea HimesErythronium howellii Erythronium howellii Howell's fawn lily Photo: CC BY, Trevor Van LoonErythronium idahoense Erythronium idahoense Liliaceae Photo: CC BY, Charles Swift all 29 ›

Names & registers

Also known as Erythronium grandiflorum var. album. (GBIF Backbone)

GBIFPOWOIPNIWFOWikidataWikipediaiNaturalist

The record

Family
Liliaceae
Described by
S.Watson
Native to
British Columbia, Oregon, Washington
Wild records
1228 in range · 299 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
Habitat climate climate answeredasked 2026-10-22
Daily extremes (NASA POWER) climate.extremes answeredasked 2026-10-22NASA POWER (MERRA-2) daily 1981–2024, cell 48.00_-123.125, lapse-corrected +860 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 25 datasets via GBIF.org; each carries its own licence.

Cultifolio

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