Tanacetum

Linnaeus

Sp. Pl. 2: 843. 1753.

,

Gen. Pl. ed. 5, 366. 1754.

Common names: Tansy tanaisie
Etymology: Derivation unknown possibly Greek athanasia, immortality, through Medieval Latin tanazita
Treatment appears in FNA Volume 19. Treatment on page 489. Mentioned on page 31, 48, 49, 52, 53, 68, 486, 488.
 TaxonIllustrator 
FNA19 P56 Tanacetum vulgare.jpegTanacetum vulgare
Achillea millefolium
Cladanthus mixtus
Yevonn Wilson-Ramsey
Linny Heagy
Yevonn Wilson-Ramsey

Perennials [annuals, subshrubs], 5–150 cm (usually rhizomatous; usually aromatic). Stems 1 or 2–5+, erect or prostrate to ascending, branched proximally and/or distally, glabrous or hairy (hairs basifixed and/or medifixed, sometimes stellate). Leaves basal and/or cauline; alternate; petiolate or sessile; blades mostly obovate to spatulate, usually 1–3-pinnately lobed, ultimate margins entire, crenate, or dentate, faces glabrous or hairy. Heads usually radiate, sometimes disciform (or quasi-radiate or radiant), usually in lax to dense, corymbiform arrays, rarely borne singly. Involucres mostly hemispheric or broader, (3–) 5–22+ mm diam. Phyllaries persistent, (20–) 30–60+ in (2–) 3–5+ series, distinct, ± ovate to oblong or oblong to lanceolate or lance-linear (sometimes carinate), unequal, margins and apices (pale to dark-brown or blackish) scarious (tips sometimes dilated). Receptacles flat to conic or hemispheric (sometimes hairy), epaleate. Ray-florets usually 10–21+ (pistillate and fertile or neuter; corollas pale-yellow to yellow or white, usually with yellowish bases [pink], laminae oblong to flabellate), sometimes 0 (in disciform or quasi-radiate or radiant heads, peripheral pistillate florets 8–30+; corollas pale-yellow, ± zygomorphic, lobes 3–4, sometimes ± raylike). Disc-florets 60–300+, bisexual, fertile; corollas yellow, tubes ± cylindric, throats narrowly funnelform to campanulate, lobes (4–) 5, ± deltate. Cypselae obconic or ± columnar (circular in cross-section), ribs (4–) 5–10 (–12+), faces usually gland-dotted, sometimes glabrous (pericarps without myxogenic cells or resin sacs, embryo-sac development tetrasporic); pappi usually coroniform, rarely 0 [distinct scales or each pappus an adaxial auricle]. x = 9 (polyploidy).

Distribution

North America, Europe, Asia, n Africa, some species widely cultivated

Discussion

Species 160 (4 in the flora).

Selected References

None.

Key

1 Leaves usually not pinnately lobed (sometimes with 1–4+ lateral lobes near bases of blades), ultimate margins ± crenate Tanacetum balsamita
1 Leaves usually 1–3-pinnately lobed, ultimate margins entire or dentate > 2
2 Leaf blades 1–2-pinnately lobed (primary lobes 3–5 pairs, ± ovate), faces (at least abaxial) usually puberulent; ray florets 10–21+ (more in "doubles"), corollas white, laminae 2–8(–12+) mm; pappi 0 or coroniform (0.1–0.2+ mm) Tanacetum parthenium
2 Leaf blades 2–3-pinnately lobed (primary lobes 4–24+ pairs, ± oblong to elliptic or linear), faces usually arachno-villous to villous, sometimes glabrescent or glabrous; ray florets 0 or 8–30+, corollas pale yellow to yellow, laminae 1–8+ mm; pappi coroniform (0.1–0.5+ mm) > 3
3 Leaves: faces glabrous or sparsely hairy; heads (disciform) 20–200 in corymbiform arrays; involucres 5–10 mm diam Tanacetum vulgare
3 Leaves: faces usually ± villous or arachno-villous to lanate, sometimes glabrescent or glabrate; heads (radiate, quasi-radiant or -radiate, or disciform) (2–)5–12(–20+) in corymbiform arrays or borne singly; involucres 8–22+ mm diam Tanacetum bipinnatum

"broader" is not a number.

... more about "Tanacetum"
not tailed +  and obtuse +
scarious +
spiciform +, racemiform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
Linda E. Watson +
Linnaeus +
decurrent +
compound +  and simple +
lobed;mostly obovate;spatulate +
Tansy +  and tanaisie +
zygomorphic +, actinomorphic +  and (3-)5-merous +
winged +  and monomorphic +
columnar +  and obconic +
fertile +  and bisexual +
fertile +  and bisexual +
North America +, Europe +, Asia +, n Africa +  and some species widely cultivated +
Derivation unknown +  and possibly Greek athanasia, immortality, through Medieval Latin tanazita +
gland-dotted +
glabrous +  and hairy +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
0.5 cm5 mm <br />0.005 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
hemispheric +
sessile +  and petiolate +
cauline +  and basal +
deltate +
entire +  and dentate +
2-carpellate +
persistent +
coroniform +
30 +  and 60 +
Sp. Pl. +  and Gen. Pl. ed. +
1753 +  and 1754 +
styliferous +, neuter +  and pistillate +
sterile +  and fertile +
bearing subulate enations +, hairy +  and bristly +
flat;conic or hemispheric +
5 +  and 10 +
exalbuminous +
prostrate +  and ascending +
hairy +  and glabrous +
2 +  and 5 +
appendaged +  and truncate +
papillate +
Compositae +
Tanacetum +
Asteraceae tribe Anthemideae +
campanulate +
cylindric +
dentate +, crenate +  and entire +
5 cm50 mm <br />0.05 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
shrub +  and subshrub +