




63 photographs › At a glance
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
Summary
Erythronium caucasicum is a bulbous perennial plant in the lily family, native to the western and central Caucasus and the Alborz Mountains in North Iran.
Quoted from Wikipedia, "Erythronium caucasicum", 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 no short rainy season: 70% of the median year's rain (1,525 mm of 2,096 mm) takes 8 months, September to March and July. Mean temperature moves 21.3 °C between the warmest and coldest month. Months are the habitat's, northern hemisphere; shifted six months for a southern-hemisphere collection: January and March to September.
Rain
2,096 mm in the median year at the habitat, 1,525 mm of it September to March and July. Wettest month November at 233 mm, driest month August at 138 mm. Across the grid cells of the range the year's total runs 1,110 mm to 2,831 mm, the 10th to 90th percentile of each cell's own year. The median of the cells' own yearly totals, 2,088 mm, is the year's rain at the top of the page; the 2,096 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: 9 to 39 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 7, the highest 90th-percentile month 41).
Warmth and air
Coldest: the 1st-percentile night over 44 years at a typical spot in the range is -11.9 °C, the absolute minimum -25.0 °C, 3,304 frost nights in 44 years, 75.1 a year (NASA POWER daily minima). Warmest: the 99th-percentile day is 37.5 °C. Monthly means: the coldest month's mean nightly low -3.3 °C in February (across the grid cells of the range -7.4 °C to 2.1 °C), the warmest month's mean daily high 25.3 °C in August (median year across the grid cells of the range, CHELSA). Cold floor: -11.9 °C, which is the 1st-percentile night over 44 years at a typical spot in the range (NASA POWER).
Relative humidity at the habitat: 60 to 63% 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 -104 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
Mean daily high from 4 °C in Jan to 25 °C in Jul and Aug; mean nightly low from -3 °C in Jan and Feb to 17 °C in Jul and Aug. The cold quarter, Dec to Feb, is the three months around the coldest month's mean nightly low, centred on the 2 months in a row that tie for it. 2,096 mm of rain in the median year (the twelve monthly medians added), the wettest month Nov. The bands show the 10th to 90th percentile across 92 habitat cells. Over 44 years at a typical spot in the range (NASA POWER) the absolute minimum was -25.0 °C and the 99th-percentile day 37.5 °C; neither is dated to a month. Beneath: daily light integral and relative humidity through the year, each on its own scale.
Figures by month
| Figure | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Day °C | 4 / -1–7 | 5 / -1–7 | 8 / 2–10 | 14 / 8–16 | 18 / 13–20 | 22 / 17–24 | 25 / 20–27 | 25 / 20–27 | 21 / 16–23 | 16 / 11–19 | 10 / 5–13 | 6 / 1–9 |
| Night °C | -3 / -8–3 | -3 / -7–2 | 0 / -5–4 | 5 / -1–8 | 10 / 4–13 | 14 / 8–17 | 17 / 12–20 | 17 / 12–21 | 12 / 8–17 | 8 / 3–13 | 2 / -3–8 | -1 / -6–5 |
| Rain mm | 212 / 113–280 | 168 / 87–239 | 171 / 86–234 | 146 / 73–206 | 142 / 87–216 | 145 / 89–202 | 152 / 82–194 | 138 / 72–173 | 166 / 80–216 | 195 / 86–266 | 233 / 115–330 | 228 / 134–312 |
| DLI | 10 / 9–12 | 16 / 15–19 | 23 / 22–26 | 30 / 29–32 | 36 / 35–37 | 39 / 37–40 | 39 / 36–41 | 36 / 33–37 | 27 / 26–28 | 19 / 17–20 | 12 / 10–13 | 9 / 7–10 |
| RH % | 62 / 59–66 | 61 / 59–64 | 60 / 59–63 | 60 / 59–61 | 61 / 60–63 | 63 / 61–64 | 62 / 59–66 | 61 / 58–65 | 61 / 59–62 | 60 / 58–62 | 60 / 58–65 | 60 / 58–66 |
How this section is made
Natural habitat
How this section is made
Photographs
Photographs: (c) Виктория Билоус, some rights reserved (CC BY); (c) Владимир Дворкин, some rights reserved (CC BY) (2); (c) Igor Balashov, some rights reserved (CC BY) (3).
Related
Similar habitat climate The 6 nearest by mean daily high, mean nightly low and rain, month by month. How.
Cyclamen coum Eastern sowbread Photo: CC BY, Asrın Akıncıoğlu
Helleborus orientalis Lenten-rose Photo: CC BY, Анна Митрошенкова
Quercus hartwissiana Strandzha Oak Photo: CC BY, Anton Popovich
Echinops ossicus Asteraceae Photo: CC BY, Илья Руденко
Crocus tommasinianus Early crocus Photo: CC BY, M. WhitsonOther Erythronium 28 in the reference
Erythronium albidum White trout lily Photo: CC0, author not stated
Erythronium americanum Yellow adder's-tongue Photo: CC BY, Patrick Jackson
Erythronium californicum California fawn-lily Photo: CC BY, gretchenparadis
Erythronium citrinum Cream Fawn Lily Photo: CC BY, Dee Shea Himes
Erythronium dens-canis Dog's-tooth-violet Photo: CC BY, Barry Stewart
Erythronium elegans Coast Range Fawn-lily Photo: CC BY, Dee Shea Himes
Erythronium grandiflorum Glacier lily Photo: CC BY, Cody Hinchliff
Erythronium helenae Pacific fawnlily Photo: CC BY, Ken-ichi Ueda
Erythronium hendersonii Henderson's fawn-lily Photo: CC BY, Dee Shea Himes
Erythronium howellii Howell's fawn lily Photo: CC BY, Trevor Van Loon
Erythronium idahoense Liliaceae Photo: CC BY, Charles Swift
Erythronium japonicum Asian fawnlily Photo: CC BY, yajapin all 29 ›Names & registers
The record
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 answeredasked 2026-10-22gbif.synonyms answeredasked 2026-10-22gbif.vernacular answeredasked 2026-10-22names fetched 2026-10-22wcvp.distribution answeredas of 2026-06-04gbif.occurrences answeredas of 2026-10-21GBIF occurrence download https://doi.org/10.15468/dl.hbdw64, of 2026-10-21; 7 records within 1 km of a botanic garden, herbarium or zoo left out (7 at a botanic garden or arboretum; Wikidata's list)climate answeredasked 2026-10-22climate.extremes answeredasked 2026-10-22NASA POWER (MERRA-2) daily 1981–2024, cell 44.50_39.375, lapse-corrected -104 m at 6.5 °C/kmwikidata answeredasked 2026-10-22wikipedia answeredasked 2026-10-22inat.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 2026-10-22inat.photos.cultivated not askedgbif.media answeredasked 2026-10-22openalex not askednot yet asked for this reference; a later fill takes the papers from OpenAlex's snapshotEvery 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 8 datasets via GBIF.org; each carries its own licence.






