Plate 1 figs. a–h · 5 observations
This species has been photographed under an open licence only 5 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.
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 22 botanical countries
| Region | TDWG code | Continent |
|---|---|---|
| Alabama | ALA | NORTHERN AMERICA |
| Arkansas | ARK | |
| Georgia | GEO | |
| Illinois | ILL | |
| Indiana | INI | |
| Iowa | IOW | |
| Kansas | KAN | |
| Kentucky | KTY | |
| Michigan | MIC | |
| Minnesota | MIN | |
| Missouri | MSO | |
| Nebraska | NEB | |
| North Carolina | NCA | |
| Ohio | OHI | |
| Oklahoma | OKL | |
| Ontario | ONT | |
| South Dakota | SDA | |
| Tennessee | TEN | |
| Texas | TEX | |
| Virginia | VRG | |
| West Virginia | WVA | |
| Wisconsin | WIS |
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 160 observations
| Condition | 5th percentile | Median | 95th percentile |
|---|---|---|---|
| Coldest month, mean daily low | -6.4 °C | -2.4 °C | 0.6 °C |
| Warmest month, mean daily high | 27.2 °C | 30.2 °C | 31.7 °C |
| Annual rainfall | 1,037 mm | 1,232 mm | 1,393 mm |
| Rainfall in the driest quarter | 201 mm | 254 mm | 287 mm |
It is found where winters bring hard frost. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 160 research-grade observations of Diarrhena americana 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 9 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.
- Diarina festucoides Raf.
- Diarina sylvatica Raf.
- Diarrhena americana var. americana
- Diarrhena arundinacea (Zea ex Lag.) Rydb.
- Diarrhena diandra Alph.Wood
- Diarrhena festucoides Fernald
- Festuca americana Michx. ex P.Beauv.
- Korycarpus diandrus Kuntze
- Roemeria zeae Roem. & Schult.
Sourcesevery claim on this page
- World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
- iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
- Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
- 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.