Euphorbia geyeriEngelm.

Geyer's sandmat

WFO wfo-0000962261 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h · 3 observations

This species has been photographed under an open licence only 3 times, so some figures below are different views of the same plant, taken on the same day, rather than different individuals. They are usually different parts of it: the leaf, the flower, the bark.

Euphorbia geyeri, photographed by Eric Knight
fig. a Eric Knight, CC BY 4.0 / 2021-07-23 / obs. 145840908

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

The specimen a real sheet, in a real collection

Herbarium
Royal Botanic Gardens, Kew
Accession
K000476501
Filed as
Euphorbia geyeri Engelm. & A.Gray
Det. by
Martínez G., M.
Collected
Pringle, C.G. 1885-08-01
Origin
MX
The sheet
View the digitised specimen (CC BY 4.0)

A real pressed plant, in a real collection, under the accession number above. Not an illustration of one. The holding institution does not serve this sheet’s image to third parties, so there is no photograph here. The record is real and the link goes to it. Where we hold no openly licensed sheet for a species this section is simply absent, and where a sheet never recorded who determined it, that field stays empty rather than being filled in. Roughly half of all herbarium sheets never recorded a determiner, which is ordinary.

Native range 21 botanical countries

Regions where Euphorbia geyeri is native: Colorado, Illinois, Indiana, Iowa, Kansas, Manitoba, Mexico Northeast, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, South Dakota, Texas, Utah, Wisconsin, Wyoming ColoradoIllinoisIndianaIowaKansasManitobaMexico NortheastMichiganMinnesotaMississippiMissouriMontanaNebraskaNew MexicoNorth DakotaOklahomaSouth DakotaTexasUtahWisconsinWyoming
Native distribution of Euphorbia geyeri, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows.
RegionTDWG codeContinent
Colorado COL NORTHERN AMERICA
Illinois ILL
Indiana INI
Iowa IOW
Kansas KAN
Manitoba MAN
Mexico Northeast MXE
Michigan MIC
Minnesota MIN
Mississippi MSI
Missouri MSO
Montana MNT
Nebraska NEB
New Mexico NWM
North Dakota NDA
Oklahoma OKL
South Dakota SDA
Texas TEX
Utah UTA
Wisconsin WIS
Wyoming WYO

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Where it actually grows measured, from 41 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -18.9 °C -9.9 °C 0.6 °C
Warmest month, mean daily high 25.3 °C 28.7 °C 33.5 °C
Annual rainfall 547 mm 890 mm 1,259 mm
Rainfall in the driest quarter 46 mm 93 mm 266 mm

It is found where winters are severely cold. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 41 research-grade observations of Euphorbia geyeri that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.

Also published as 6 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

  • Anisophyllum geyeri Klotzsch & Garcke
  • Chamaesyce geyeri (Engelm.) Small
  • Chamaesyce geyeri var. wheeleriana (Warnock & M.C.Johnst.) Mayfield
  • Chamaesyce polyclada Small
  • Euphorbia geyeri var. microsperma A.Gray
  • Euphorbia polyclada Boiss.

Sourcesevery claim on this page

  1. World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
  2. iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
  3. USDA PLANTS Database. common name, checklist symbol CHGE2. public domain. Retrieved 2026-07-13.
  4. Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.