




73 photographs › At a glance
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Summary
Ulmus americana, generally known as the American elm or, less commonly, as the white elm or water elm, is a species of elm native to eastern North America. The trees can live for several hundred years. It is a very hardy species that can withstand low winter temperatures. The American elm was once exceptionally common as a street tree, its tolerance of urban conditions making it a popular choice to line American streets in the 19th and early 20th centuries. More on Wikipedia ›
Quoted from Wikipedia, "Ulmus americana", CC BY-SA 4.0.
Cultivation
Seasons
The rain rule reads no short rainy season: 70% of the median year's rain (761 mm of 1,046 mm) takes 8 months, April to November. Mean temperature moves 26.4 °C between the warmest and coldest month. Months are the habitat's, northern hemisphere; shifted six months for a southern-hemisphere collection: October to May.
Rain
1,046 mm in the median year at the habitat, 761 mm of it April to November. Wettest month June at 106 mm, driest month February at 65 mm. Across the grid cells of the range the year's total runs 842 mm to 1,308 mm, the 10th to 90th percentile of each cell's own year. The median of the cells' own yearly totals, 1,030 mm, is the year's rain at the top of the page; the 1,046 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: 10 to 40 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 8, the highest 90th-percentile month 44).
Warmth and air
Coldest: the 1st-percentile night over 44 years at a typical spot in the range is -19.5 °C, the absolute minimum -30.4 °C, 6,244 frost nights in 44 years, 141.9 a year (NASA POWER daily minima). Warmest: the 99th-percentile day is 34.7 °C. Monthly means: the coldest month's mean nightly low -7.3 °C in January (across the grid cells of the range -14.6 °C to 4.4 °C), the warmest month's mean daily high 27.5 °C in July (median year across the grid cells of the range, CHELSA). Cold floor: -19.5 °C, which is the 1st-percentile night over 44 years at a typical spot in the range (NASA POWER).
Relative humidity at the habitat: 56 to 61% 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 -154 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, northern hemisphere
Mean daily high from 0 °C in Jan to 28 °C in Jul; mean nightly low from -7 °C in Jan to 18 °C in Jul and Aug. The cold quarter, Dec to Feb, is the three months around the coldest month's mean nightly low. 1,046 mm of rain in the median year (the twelve monthly medians added), the wettest month Jun. The bands show the 10th to 90th percentile across 860 habitat cells. Over 44 years at a typical spot in the range (NASA POWER) the absolute minimum was -30.4 °C and the 99th-percentile day 34.7 °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 | 0 / -5–15 | 2 / -3–17 | 8 / 3–21 | 14 / 10–25 | 20 / 17–29 | 25 / 22–32 | 28 / 25–34 | 27 / 24–34 | 22 / 19–31 | 16 / 12–26 | 9 / 5–20 | 2 / -2–15 |
| Night °C | -7 / -15–4 | -6 / -13–6 | -2 / -7–10 | 4 / 0–14 | 10 / 7–19 | 16 / 13–23 | 18 / 16–25 | 18 / 15–25 | 14 / 11–21 | 8 / 5–16 | 2 / -2–10 | -4 / -10–6 |
| Rain mm | 69 / 27–94 | 65 / 33–89 | 74 / 48–108 | 85 / 65–109 | 101 / 79–134 | 106 / 85–128 | 101 / 61–128 | 94 / 54–119 | 93 / 75–115 | 95 / 70–124 | 86 / 52–114 | 77 / 36–108 |
| DLI | 12 / 10–19 | 19 / 17–23 | 26 / 25–29 | 32 / 30–36 | 37 / 35–39 | 40 / 38–42 | 39 / 37–44 | 34 / 32–40 | 27 / 24–33 | 19 / 16–26 | 12 / 9–20 | 10 / 8–17 |
| RH % | 61 / 57–64 | 59 / 56–62 | 57 / 55–59 | 56 / 54–57 | 57 / 55–59 | 58 / 57–61 | 58 / 55–61 | 59 / 54–62 | 59 / 55–61 | 58 / 56–61 | 59 / 57–62 | 61 / 57–65 |
How this section is made
Natural habitat
How this section is made
Photographs
Photographs: (c) The Wrong Industry, some rights reserved (CC BY); (c) Andrew Sebastian, some rights reserved (CC BY) (2); (c) Chris Poling, some rights reserved (CC BY) (2); (c) Diane Auberson-Lavoie, some rights reserved (CC BY).
Related
Similar habitat climate The 6 nearest by mean daily high, mean nightly low and rain, month by month. How.
Carex granularis Limestone meadow sedge Photo: CC0, author not stated
Rubus occidentalis Black raspberry Photo: CC BY, Dmitriy Bochkov
Carex vulpinoidea American fox-sedge Photo: CC0, author not stated
Heteranthera dubia Water star-grass Photo: CC BY, Jeff Clark
Solidago nemoralis Grey goldenrod Photo: CC0, author not stated
Filipendula rubra Queen-of-the-prairie Photo: CC0, author not statedOther Ulmus 27 in the reference
Ulmus alata Winged elm Photo: CC BY, C Fishtahler
Ulmus × androssowii Narwan Photo: CC0, Pedro
Ulmus crassifolia Cedar elm Photo: CC BY, Linda Jo Conn
Ulmus davidiana Japanese elm Photo: CC BY, Станислав Чуванов
Ulmus glabra Wych elm Photo: CC BY, Cyndy Sims (Parr)
Ulmus × intermedia Ulmaceae Photo: CC BY, Brandon Corder all 28 ›Names & registers
Also known as Ulmus alba; Ulmus americana f. alba; Ulmus americana f. americana; Ulmus americana f. ascendens; Ulmus americana f. columnaris and 18 more. (GBIF Backbone)
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; 154 records within 1 km of a botanic garden, herbarium or zoo left out (90 at a botanic garden or arboretum, 5 at a herbarium, 59 at a zoo; Wikidata's list)climate answeredasked 2026-10-22climate.extremes answeredasked 2026-10-22NASA POWER (MERRA-2) daily 1981–2024, cell 43.50_-80.000, lapse-corrected -154 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 89 datasets via GBIF.org; each carries its own licence.






