Tanacetum achilleifolium

Plate 1 figs. a–h · 8 separate observations

Tanacetum achilleifolium, photographed by Konstantin Grebennikov — fig. b Konstantin Grebennikov, CC BY 4.0 / obs. 132544246

Tanacetum achilleifolium, photographed by Andrew Bazdyrev — fig. d Andrew Bazdyrev, CC BY 4.0 / obs. 77614914

Tanacetum achilleifolium, photographed by Svetlana Polevova — fig. e Svetlana Polevova, CC0 1.0 / obs. 73713226

Tanacetum achilleifolium, photographed by Иван Пристрем — fig. f Иван Пристрем, CC BY 4.0 / obs. 180467866

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: Smithsonian, US National Herbarium
Accession: US 249566
Filed as: Tanacetum achilleifolium (M.Bieb.) Sch.Bip.
Det. by: not recorded on this sheet
Collected: Hohenacker
Origin: ZZ
The sheet: View the digitised specimen (CC0 1.0)

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 9 botanical countries

Native distribution of Tanacetum achilleifolium, 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
Bulgaria	BUL	EUROPE
Central European Russia	RUC
East European Russia	RUE
Krym	KRY
Romania	ROM
South European Russia	RUS
Ukraine	UKR
Kazakhstan	KAZ	ASIA-TEMPERATE
North Caucasus	NCS

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 42 in flower of 48 examined

92%

90%

Proportion of examined Tanacetum achilleifolium 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	2	too few examined
May	12	13	92%	67% to 99%
Jun	26	29	90%	74% to 96%
Jul	3	3	too few examined
Aug	0	0	too few examined
Sep	0	0	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 Tanacetum achilleifolium 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. 42 of 48 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 10 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 555 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	-16.9 °C	-7.5 °C	0.2 °C
Warmest month, mean daily high	25.5 °C	29.5 °C	31.5 °C
Annual rainfall	274 mm	386 mm	647 mm
Rainfall in the driest quarter	48 mm	74 mm	126 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 555 research-grade observations of Tanacetum achilleifolium 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 8 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.

Chamaemelum achilleifolium (M.Bieb.) E.H.L.Krause
Chrysanthemum achilleaefolium DC.
Chrysanthemum achilleifolium DC.
Chrysanthemum achilleifolium (M.Bieb.) Kuntze
Gymnocline vaillantii Cass.
Gymnocline xanthocephala Cass.
Pyrethrum achilleifolium M.Bieb.
Pyrethrum achilleifolium var. achilleifolium

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.
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.