Astragalus miser (timber milkvetch)

Plate 1 figs. a–h · 8 separate observations

Astragalus miser, photographed by machaut2 — fig. a machaut2, CC BY 4.0 / 2022-06-10 / obs. 205054731

Astragalus miser, photographed by Shane Johnson — fig. b Shane Johnson, CC0 1.0 / obs. 204540731

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 12 botanical countries

Native distribution of Astragalus miser, 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.

Region	TDWG code	Continent
Alberta	ABT	NORTHERN AMERICA
Arizona	ARI
British Columbia	BRC
Colorado	COL
Idaho	IDA
Montana	MNT
Nevada	NEV
New Mexico	NWM
South Dakota	SDA
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 235 in flower of 263 examined

60%

96%

93%

79%

43%

Proportion of examined Astragalus miser 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	3	5	60%	23% to 88%
May	75	78	96%	89% to 99%
Jun	112	120	93%	87% to 97%
Jul	38	48	79%	66% to 88%
Aug	3	7	43%	16% to 75%
Sep	2	3	too few examined
Oct	1	1	too few examined
Nov	1	1	too few examined
Dec	0	0	too few examined

Peak flowering in May. Each bar is the share of Astragalus miser 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. 235 of 263 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 7 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 2,014 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	-15.1 °C	-9.5 °C	-5.3 °C
Warmest month, mean daily high	20.3 °C	25.3 °C	28.2 °C
Annual rainfall	348 mm	444 mm	871 mm
Rainfall in the driest quarter	50 mm	76 mm	154 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 2,014 research-grade observations of Astragalus miser 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 46 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.

Astragalus campestris var. crispatus M.E.Jones
Astragalus campestris var. decumbens (Torr. & A.Gray) M.E.Jones
Astragalus campestris var. hylophilus (Rydb.) M.E.Jones
Astragalus campestris var. serotinus (A.Gray ex E.Cooper) M.E.Jones
Astragalus carltonii J.F.Macbr.
Astragalus convallarius var. hylophilus (Rydb.) Tidestr.
Astragalus decumbens (Nutt.) A.Gray
Astragalus decumbens var. crispatus (M.E.Jones) Barneby
Astragalus decumbens var. decurrens (Rydb.) Cronquist
Astragalus decumbens var. oblongifolius (Rydb.) Cronquist
Astragalus decumbens var. serotinus (A.Gray ex E.Cooper) M.E.Jones
Astragalus divergens Blank.
Astragalus garrettii J.F.Macbr.
Astragalus griseopubescens E.Sheld.
Astragalus hylophilus (Rydb.) A.Nelson
Astragalus hylophilus var. oblongifolius (Rydb.) J.F.Macbr.
Astragalus miser var. decurrens (Rydb.) Cronquist
Astragalus palliseri A.Gray
Astragalus rydbergii J.F.Macbr.
Astragalus serotinus A.Gray ex E.Cooper
Astragalus serotinus var. palliseri (A.Gray) J.F.Macbr.
Homalobus camporum Rydb.
Homalobus decumbens Nutt.
Homalobus decurrens Rydb.

and 22 more.

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.
USDA PLANTS Database. common name, checklist symbol ASMI9. public domain. 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.