Pyrethum Daisy

Foodplant / pathogen
Aphelenchoides ritzemabosi infects and damages limp, discoloured leaf of Tanacetum coccineum

In Great Britain and/or Ireland:
Foodplant / parasite
Golovinomyces cichoracearum parasitises live Tanacetum coccineum

Foodplant / parasite
mostly hypophyllous uredium of Puccinia tanaceti parasitises live leaf of Tanacetum coccineum
Remarks: season: 7-9

Foodplant / spot causer
amphigenous colony of Ramularia hyphomycetous anamorph of Ramularia bellunensis causes spots on live leaf of Tanacetum coccineum

Perennial subshrub with ± subglabrous to bifurcate hairy, 20 – 60 cm tall, erect or ascending, sparsely foliated, mostly simple shoots from branched suberect rhizome. Leaves on 2 – 10 cm long petioles or subsessile, subglabrous on both sides, laminas ovate to oblong-elliptic, 4 – 8 cm long, 2.5 – 4 cm broad, basal and lower stem leaves 2-pinnatisect into deltoid-elliptic or linear-lanceolate, 4 – 8 x 0.5 – 1 mm, acuminate ultimate segments, mid-stem and uppr leaves gradually smaller, shortly petioled to sessile, unipinnate to entire, acute. Capitula radiate, solitary, terminal, on 10 – 20 cm long, ± hairy peduncles. Involucre coryliform, 4-seriate, phyllaries with broad, dark brown to blackish membranous margins, sparsely hairy to glabrous outside, outermost lanceolate, c. 3.5 mm long, median and inner ones narrowly elliptic to linear-oblanceolate, 4.5 – 5.5 mm long, ± obtuse. Ray-florets up to 30, with pale-pink to reddish-pink, 10 – 25 x 3.5 – 4 mm, apically 2-3-dented ligules. Disc-florets yellow, with 2.5 – 3.5 mm long, yellow, 5-toothed corolla tube. Cypselas pale-brown, 2.5 – 3.5 mm long, 5-10-ribbed. Pappus coroniform, 0.1 – 0.2 mm long, entire or shallowly obtuse lobed.

Distribution: Turkey, Georgia, Caucasus, Armenia, Iraq (Kurdistan); introduced in several countries in temperate climates.

Fl. Per.: June-September.

It is cultivated for obtaining insecticidal powder, “Pyrethrum”.

Chrysanthemum coccineum Willd., Sp. Pl. 3: 2144. 1803; R. R. Stewart, l. c. 731; C. roseum Adams in Weber & Mohr, Beitr. Naturk. 1: 70. 1805; Pyrethrum roseum (Adams) M. Bieb., Fl. Taur. Cauc. 2: 324. 1808; Tanacetum roseum (Adams) Schultz-Bip., Tanacet. 58. 1844; Pyrethrum coccineum (Willd.) Worosch. in Spisok. Sem. Gl. Bot. Sada. Akad. Nauk. SSSR 9: 21. 1954; Tzvelev in Schischk. & Bobrov, l. c. 210.