''Tanacetum'' is a genus of about 160 species of

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

s in the aster family,

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

, native to many regions of the

Northern Hemisphere The Northern Hemisphere is the half of Earth that is north of the equator. For other planets in the Solar System, north is defined by humans as being in the same celestial sphere, celestial hemisphere relative to the invariable plane of the Solar ...

.''Tanacetum''.
Flora of North America. They are known commonly as tansies.''Tanacetum''.
Integrated Taxonomic Information System (ITIS). The name tansy can refer specifically to ''

Tanacetum vulgare Tansy (''Tanacetum vulgare'') is a perennial, herbaceous flowering plant in the genus ''Tanacetum'' in the Asteraceae, aster family, native to temperate Europe and Asia. It has been introduced to other parts of the world, including North Ameri ...

'', which may be called the common tansy or garden tansy for clarity. The generic name ''Tanacetum'' means 'immortality' in

Botanical Latin Botanical Latin is a technical language based on Neo-Latin, used for descriptions of botanical taxa. From 1935 to 2011, the International Code of Botanical Nomenclature mandated Botanical Latin to be used for the descriptions of new taxa (other tha ...

, since tansy was once placed between the burial sheets of the dead to repel vermin. Other familiar species include costmary (''T. balsamita'') and

feverfew ''Tanacetum parthenium'', known as feverfew, is a flowering plant in the daisy family, Asteraceae. It may be grown as an ornament, and may be identified by its synonyms, ''Chrysanthemum parthenium'' and ''Pyrethrum parthenium''. Having its ...

(''T. parthenium''). Tansies are mainly perennial herbs, but some are annuals and subshrubs. Some are a few centimeters tall and some reach . They vary in form, with one or more branching stems growing erect or prostrate, usually from

rhizome In botany and dendrology, a rhizome ( ) is a modified subterranean plant stem that sends out roots and Shoot (botany), shoots from its Node (botany), nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from ...

s. They are hairy to hairless in texture, and most are aromatic. The leaves are alternately arranged, the blades sometimes borne on petioles. They are usually deeply lobed and may have toothed edges. Most species have flowers in loose or dense

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

s. The flower has layers of distinct

phyllaries In botanical terminology, a phyllary, also known an involucral bract or tegule, is a single bract of the involucre of a composite flower. The involucre is the grouping of bracts together. Phyllaries are reduced leaf-like structures that form one o ...

around its base and may be flat to hemispheric in shape. The flower has many yellow disc florets, sometimes over 300. Some species have ray florets in shades of yellow, or white with yellowish bases. Some species lack true ray florets but have flat yellowish disc florets that look like rays. The fruit is a ribbed, glandular cypsela, usually with a pappus on the end.

Selected species

Species include: *'' Tanacetum abrotanifolium'' (L.) Druce *''

Tanacetum abrotanoides ''Tanacetum'' is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere.

'' *''

Tanacetum achilleifolium ''Tanacetum'' is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere.

'' (M. Bieb.) Sch. Bip. *''

Tanacetum alatavicum ''Tanacetum'' is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere.

'' *''

Tanacetum annuum ''Tanacetum'' is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere.

'' – Moroccan Tansy, Blue Tansy *''

Tanacetum argenteum ''Tanacetum'' is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere.

'' (Lam.) Willd. *''

Tanacetum atkinsonii ''Tanacetum'' is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere.

'' (C.B.Clarke) Kitam. *'' Tanacetum balsamita'' L. – costmary *''

Tanacetum bipinnatum ''Tanacetum'' is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere.

'' (L.) Sch. Bip. – Lake Huron tansy, camphor tansy *''

Tanacetum camphoratum ''Tanacetum camphoratum'' is a species of flowering plant in the aster family known by the common names camphor tansy and dune tansy. Taxonomy It was formerly known as ''Tanacetum douglasii'', now a synonym, and is often included in '' T. bip ...

'' Less. – dune tansy *''

Tanacetum cinerariifolium ''Tanacetum cinerariifolium'' is a species of flowering plant in the aster family, Asteraceae, and formerly part of the genus ''Pyrethrum'', but now placed in the genus ''Chrysanthemum'', or the genus ''Tanacetum'' by some biologists. It is calle ...

'' (Trevir.) Sch. Bip. – Dalmatian insect-flower, Dalmatian pyrethrum *''

Tanacetum coccineum ''Tanacetum'' is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere.

'' (Willd.) Grierson – garden pyrethrum, painted daisy, Persian insect-flower, Persian chrysanthemum Image of ''Tanacetum coccineum chamaemelifolium''
in sciencephoto.com *'' Tanacetum corymbosum'' (L.) Sch. Bip. – scentless feverfew, corymbflower tansy *''

Tanacetum densum ''Tanacetum'' is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere.

'' (Labill.) Sch. Bip. *'' Tanacetum falconeri'' *'' Tanacetum ferulaceum'' (Sch. Bip.) Walp. *'' Tanacetum haradjanii'' (Rech. f.) Grierson *'' Tanacetum kaschgarianum'' *'' Tanacetum krylovianum'' *'' Tanacetum macrophyllum'' (Waldst. & Kit.) Sch. Bip. – rayed tansy *'' Tanacetum microphyllum'' DC. *''

Tanacetum niveum ''Tanacetum'' is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere.

'' *'' Tanacetum parthenifolium'' (Willd.) Sch. Bip. *''

Tanacetum parthenium ''Tanacetum parthenium'', known as feverfew, is a flowering plant in the daisy family, Asteraceae. It may be grown as an ornament, and may be identified by its synonyms, ''Chrysanthemum parthenium'' and ''Pyrethrum parthenium''. Having its ...

'' (L.) Sch. Bip. – feverfew *'' Tanacetum pinnatum'' *'' Tanacetum polycephalum'' *'' Tanacetum poteriifolium'' (Nordm.) Grierson *'' Tanacetum praeteritium'' (Horw.) Heywood *'' Tanacetum ptarmiciflorum'' (Webb) Sch. Bip. – dusty-miller, silver-lace *'' Tanacetum pulchrum'' *'' Tanacetum richterioides'' *'' Tanacetum santolina'' *''

Tanacetum scopulorum ''Tanacetum'' is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere.

'' *'' Tanacetum tanacetoides'' *'' Tanacetum tatsienense'' *''

'' L. – common tansy, garden tansy, golden-buttons

Gallery of species

File:Tanacetum balsamita 02.jpg, File:Tanacetumcamphoratum1.jpg, File:Tanacetum_cinerariifolium_-_Köhler–s_Medizinal-Pflanzen-269.jpg, File:Tanacetum_coccineum_-_Köhler–s_Medizinal-Pflanzen-037.jpg, File:Tanacetum corymbosum2 W.jpg, File:Tanacetum densum ssp. siasicum GotBot 2015.jpg, File:Tanacetum ferulaceum kz1.JPG, File:Chrysanthemum haradjanii 1.jpg, File:Tanacetum huronense.jpg, File:Tanacetum_macrophyllum-Stueber.jpg, File:Tanacetum niveum 'jackpot' 3.JPG, File:Tanacetum parthenium0.jpg, File:Tanacetum ptarmiciflorum 'Silver Feather' 2.JPG, File:Tanacetum siculum 0119.JPG, File:Pietaryrtti.jpg,

References

* * {{Authority control Asteraceae genera Taxa named by Carl Linnaeus