Ladeania lanceolata(Pursh) Reveal & A.N.Egan

lemon scurfpea

WFO wfo-0001286865 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h · 8 separate observations

Ladeania lanceolata, photographed by mark-groeneveld
fig. a mark-groeneveld, CC BY 4.0 / 2022-05-19 / obs. 198988655

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.

Native range 17 botanical countries

Regions where Ladeania lanceolata is native: Arizona, California, Colorado, Idaho, Kansas, Montana, Nebraska, Nevada, New Mexico, North Dakota, Oklahoma, Oregon, South Dakota, Texas, Utah, Washington, Wyoming ArizonaCaliforniaColoradoIdahoKansasMontanaNebraskaNevadaNew MexicoNorth DakotaOklahomaOregonSouth DakotaTexasUtahWashingtonWyoming
Native distribution of Ladeania lanceolata, 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
Arizona ARI NORTHERN AMERICA
California CAL
Colorado COL
Idaho IDA
Kansas KAN
Montana MNT
Nebraska NEB
Nevada NEV
New Mexico NWM
North Dakota NDA
Oklahoma OKL
Oregon ORE
South Dakota SDA
Texas TEX
Utah UTA
Washington WAS
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.

Flowering 43 in flower of 59 examined

Proportion of examined Ladeania lanceolata in flower, by month
Month In flower Examined Share 95% interval
Jan 0 0 too few examined
Feb 0 0 too few examined
Mar 0 0 too few examined
Apr 0 4 too few examined
May 12 12 100% 76% to 100%
Jun 16 20 80% 58% to 92%
Jul 10 15 67% 42% to 85%
Aug 3 5 60% 23% to 88%
Sep 1 2 too few examined
Oct 1 1 too few examined
Nov 0 0 too few examined
Dec 0 0 too few examined

Peak flowering in May. Each bar is the share of Ladeania lanceolata observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 43 of 59 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 8 months have fewer than 5 examined observations, so no proportion is drawn for them. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.cgje2x.

Where it actually grows measured, from 481 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -18.3 °C -8.4 °C -1.6 °C
Warmest month, mean daily high 24.9 °C 29.3 °C 34.3 °C
Annual rainfall 182 mm 349 mm 511 mm
Rainfall in the driest quarter 19 mm 37 mm 59 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 481 research-grade observations of Ladeania lanceolata 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. Climate from CHELSA V2.1 (Karger et al. 2017); occurrences from 10.15468/dl.cgje2x.

Also published as 27 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.

  • Lotodes elliptica var. angustissima Kuntze
  • Lotodes elliptica var. latifolia Kuntze
  • Lotodes ellipticum (Pursh) Kuntze
  • Lotodes micranthum (A.Gray) Kuntze
  • Psoralea arenaria Nutt.
  • Psoralea elliptica Pursh
  • Psoralea lanceolata Pursh
  • Psoralea lanceolata subsp. scabra (Nutt.) Piper
  • Psoralea lanceolata var. lanceolata
  • Psoralea lanceolata var. purshii (Vail) Piper
  • Psoralea lanceolata var. scabra (Nutt.) Piper
  • Psoralea lanceolata var. stenophylla (Rydb.) Toft & S.L.Welsh
  • Psoralea lanceolata var. stenostachys (Rydb.) S.L.Welsh
  • Psoralea laxiflora Nutt.
  • Psoralea micrantha A.Gray
  • Psoralea purshii Vail
  • Psoralea scabra Nutt.
  • Psoralea stenophylla Rydb.
  • Psoralea stenostachys Rydb.
  • Psoralidium lanceolatum (Pursh) Rydb.
  • Psoralidium lanceolatum var. stenophyllum (Rydb.) S.L.Welsh
  • Psoralidium lanceolatum var. stenophyllum (Rydb.) C.A.Toft & S.L.Welsh
  • Psoralidium lanceolatum var. stenostachys (Rydb.) S.L.Welsh
  • Psoralidium micranthum (A.Gray) Rydb.

and 3 more.

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 PSLA3. 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.