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Boehmeria cylindrica; photograph (c) Thomas Boe, some rights reserved (CC BY) CC BY(c) Thomas Boe, some rights reserved (CC BY) · observed growing wild · 2026-09-22

Boehmeria cylindrica (L.) Sw.

Small-spike false nettle; Bog-hemp; False nettle; Swamp-nettle

Urticaceae · New Brunswick, Ontario +73

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Boehmeria cylindrica, photograph author not stated, no rights reservedBoehmeria cylindrica, photograph (c) Shanze Yoell, some rights reserved (CC BY)Boehmeria cylindrica, photograph (c) Shanze Yoell, some rights reserved (CC BY)Boehmeria cylindrica, photograph (c) Shanze Yoell, some rights reserved (CC BY)Boehmeria cylindrica, photograph (c) Carter Ertel, some rights reserved (CC BY)Boehmeria cylindrica, photograph (c) Brandon Corder, some rights reserved (CC BY) 72 photographs ›
Habitat figures
Cold floor (1 night in 100)
-12.1°C
Record low -25.6 °C in 44 years, at a typical spot in the range NASA POWER
Warmest month, mean daily high
30°C
Jul at the habitat CHELSA
Rain a year (median across the range)
1,192mm
12 months of 25 mm or more in the median year CHELSA
Open-sky light
13–40DLI
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
Rain spread: 70% of the median year's rain takes 8 months, so no short rainy season. rain rule, CHELSA
Northern hemisphere unless you set your site. The chart is in the habitat's months.

Summary

Boehmeria cylindrica, with common names false nettle and bog hemp, is an herb in the family Urticaceae. It is widespread in eastern North America and the Great Plains from New Brunswick to Florida to Texas to Nebraska, with scattered reports of isolated populations in New Mexico, Arizona, and Utah, as well as in Bermuda, Mexico, Central America, the West Indies, and South America.

Quoted from Wikipedia, "Boehmeria cylindrica", CC BY-SA 4.0.

Cultivation

Seasons

The rain rule reads no short rainy season: 70% of the median year's rain (820 mm of 1,157 mm) takes 8 months, March to October. Mean temperature moves 24.2 °C between the warmest and coldest month. Months are the habitat's, northern hemisphere; shifted six months for a southern-hemisphere collection: September to April.

Rain

1,157 mm in the median year at the habitat, 820 mm of it March to October. Wettest month July at 113 mm, driest month February at 76 mm. Across the grid cells of the range the year's total runs 916 mm to 1,466 mm, the 10th to 90th percentile of each cell's own year. The median of the cells' own yearly totals, 1,192 mm, is the year's rain at the top of the page; the 1,157 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: 13 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 9, the highest 90th-percentile month 42).

Warmth and air
Temperature

Coldest: the 1st-percentile night over 44 years at a typical spot in the range is -12.1 °C, the absolute minimum -25.6 °C, 4,296 frost nights in 44 years, 97.6 a year (NASA POWER daily minima). Warmest: the 99th-percentile day is 36.7 °C. Monthly means: the coldest month's mean nightly low -2.6 °C in January (across the grid cells of the range -10.9 °C to 7.1 °C), the warmest month's mean daily high 29.8 °C in July (median year across the grid cells of the range, CHELSA). Cold floor: -12.1 °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: 56 to 60% 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 -93 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

Habitat climate of Boehmeria cylindrica through the yearWarmest month July, mean daily high 30 °C; coldest month January, mean nightly low -2.6 °C; 1,157 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.-40°-20°0°20°40°frost36.7° 99th-percentile day, NASA POWER-25.6° lowest night in 44 years, NASA POWER°C · day and nightcold quarter050100150200mm rainDLI 13–40RH 56–60%JanFebMarAprMayJunJulAugSepOctNovDec
day night rain medians and 10th–90th percentile across 1329 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 °C6 / -2–178 / -1–1813 / 5–2218 / 12–2523 / 19–2928 / 24–3130 / 26–3329 / 25–3225 / 21–3019 / 14–2613 / 7–217 / 1–17
Night °C-3 / -11–7-1 / -10–93 / -5–128 / 2–1513 / 9–2018 / 14–2321 / 17–2420 / 17–2416 / 13–2210 / 6–175 / 0–120 / -7–8
Rain mm82 / 45–11776 / 49–12598 / 59–12993 / 71–121107 / 86–139111 / 92–164113 / 89–159102 / 78–170102 / 83–14094 / 75–12590 / 63–12289 / 51–129
DLI15 / 11–1920 / 17–2427 / 25–3134 / 32–3837 / 36–4040 / 38–4139 / 38–4234 / 33–3829 / 26–3222 / 18–2715 / 11–2113 / 9–18
RH %58 / 56–6357 / 55–6156 / 55–5856 / 54–5857 / 56–6059 / 57–6259 / 57–6260 / 57–6359 / 57–6258 / 56–6058 / 57–6159 / 57–63
How this section is made
Each figure is the median across the 1329 grid cells on land that hold in-range records (1524 records in those cells; 6 more cells hold records but no land by the elevation layer, so those records sit at sea and the cells are 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 1048:2012 (37.575, -79.375). Over 44 years there: absolute minimum -25.6 °C, 1st-percentile night -12.1 °C, 99th-percentile day 36.7 °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 1329 distinct grid cells holding 1524 of the 1530 in-range records (6 further cells with records at sea, by the elevation layer, left out); extremes and elevation at the typical cell 1048:2012 (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 37.50_-79.375, lapse-corrected -93 m at 6.5 °C/km. Elevation: ETOPO 2022, 270 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.
NativeNew Brunswick, Ontario, Québec, Illinois, Iowa, Kansas, Minnesota, Missouri, Nebraska, Oklahoma, South Dakota, Wisconsin, Connecticut, Indiana, Maine, Massachusetts, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode I., Vermont, West Virginia, Arizona, Utah, New Mexico, Texas, Alabama, Arkansas, Delaware, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, District of Columbia, Mexico Central, Mexico Northeast, Mexico Gulf, Mexico Southwest, Mexico Southeast, Belize, Costa Rica, Guatemala, Honduras, Nicaragua, Panama, Bermuda, Cuba, Dominican Republic, Haiti, Jamaica, Puerto Rico, Trinidad-Tobago, French Guiana, Surinam, Venezuela, Bolivia, Colombia, Ecuador, Brazil West-Central, Brazil Northeast, Brazil Southeast, Brazil North, Brazil South, Argentina Northeast, Paraguay, Uruguay · introduced: France · 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 marker38.798, -77.221 · in the densest population, 251 records (13% of those in range)
Extinct inWindward Is. · recorded as extinct by WCVP: history, not habitat; no records are tested against these regions
Kew's description“subshrub or shrub” · “subtropical” · quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Evidence usedThe map marker rests on all 1866 georeferenced records inside the native range; the climate across the range on the 1524 of them in the land cells it reads, of 1530 placed to within 10 km; the map shows only the 652 openly licensed ones, which alone would put the marker 9 km away. 12 records outside the WCVP native range not used. 336 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 1866 in-range records; it decides nothing. Records outside the native range, living specimens and records marked introduced are not used; which records count.

Photographs

Boehmeria cylindrica, photograph 1did not loadBoehmeria cylindrica, photograph 2did not loadBoehmeria cylindrica, photograph 3did not loadBoehmeria cylindrica, photograph 4did not loadBoehmeria cylindrica, photograph 5did not loadBoehmeria cylindrica, photograph 6did not load

Photographs: author not stated, no rights reserved · CC0; (c) Shanze Yoell, some rights reserved (CC BY) (3); (c) Carter Ertel, some rights reserved (CC BY); (c) Brandon Corder, some rights reserved (CC BY).

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

Desmodium paniculatum Desmodium paniculatum Narrow-leaf tick-trefoil Photo: CC BY, 岸本年郎Betula nigra Betula nigra River birch Photo: CC0, author not statedCornus florida Cornus florida Flowering dogwood Photo: CC0, author not statedSisyrinchium angustifolium Sisyrinchium angustifolium Narrow-leaf blue-eyed-grass Photo: CC BY, Matt PelikanPlatanus occidentalis Platanus occidentalis American sycamore Photo: CC BY, Michael A. ThaibinhAsimina triloba Asimina triloba Pawpaw Photo: CC0, author not stated

Other Boehmeria 12 in the reference

Boehmeria caudata Boehmeria caudata Urticaceae Photo: CC BY, Daniel Duarte Boehmeria celtidifolia Urticaceae Boehmeria densiflora Boehmeria densiflora Dense-flowered False Nettle Photo: CC0, author not statedBoehmeria excelsa Boehmeria excelsa Urticaceae Photo: CC BY, Flavien SaboureauBoehmeria holosericea Boehmeria holosericea Seashore falsenettle Photo: CC BY, pavlaki1968Boehmeria japonica Boehmeria japonica Large-leaf falsenettle Photo: CC BY, 曾昱承 Yu-Cheng ZengBoehmeria nivea Boehmeria nivea China-grass Photo: CC BY, ITÔ, HirokiBoehmeria pilosiuscula Boehmeria pilosiuscula Urticaceae Photo: CC BY, Yu-Huang WangBoehmeria sieboldiana Boehmeria sieboldiana Siebold’s falsenettle Photo: CC BY, 黃美滿Boehmeria splitgerbera Boehmeria splitgerbera Urticaceae Photo: CC0, author not statedBoehmeria virgata Boehmeria virgata Native ramie Photo: CC BY, Bryce Watts-ParkerBoehmeria zollingeriana Boehmeria zollingeriana Zollinger's False Nettle Photo: CC BY, 謝麗霦

Names & registers

Also known as Boehmeria atrovirens; Boehmeria austrina; Boehmeria cylindrica f. cuneata; Boehmeria cylindrica subsp. phyllostachya; Boehmeria cylindrica var. brachystachys and 34 more. (GBIF Backbone)

GBIFPOWOIPNIWFOWikidataWikipediaiNaturalist

The record

Family
Urticaceae
Described by
(L.) Sw.
Native to
New Brunswick, Ontario, Québec +72
Wild records
1866 in range · 652 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 2026-10-21
GBIF species record gbif.species answeredasked 2026-10-21
GBIF synonyms gbif.synonyms answeredasked 2026-10-21
GBIF common names gbif.vernacular answeredasked 2026-10-21names fetched 2026-10-21
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; 58 records within 1 km of a botanic garden, herbarium or zoo left out (46 at a botanic garden or arboretum, 2 at a herbarium, 10 at a zoo; Wikidata's list)
Habitat climate climate answeredasked 2026-10-21
Daily extremes (NASA POWER) climate.extremes answeredasked 2026-10-21NASA POWER (MERRA-2) daily 1981–2024, cell 37.50_-79.375, lapse-corrected -93 m at 6.5 °C/km
Wikidata wikidata answeredasked 2026-10-21
Wikipedia wikipedia answeredasked 2026-10-21
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 2026-10-21
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 131 datasets via GBIF.org; each carries its own licence.

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