Achillea L.

Herbs or undershrubs, perennial, pilose or pubescent, often with thick woody rootstock. Leaves alternate, serrulate, pinnatisect or pinnatipartite. Heads heterogamous, radiate, peduncled or subsessile, small or medium sized, usually arranged in terminal corymbs, rarely solitary, terminal. Involucral bracts few seriate, more or less scarious margined, Receptacle flat or convex, paleaceus; paleae lanceolate or oblong. Ray florets female; lingule white pink or yellow, short, more or less 3-dentate. Disc florets hermaphrodite, fertile, tubular, compressed and 2-winged; limbs 5-toothed. Anther bases obtuse. Style arms of disc florets with truncate and penicillate tips. Achenes glabrous, smooth, compressed, not winged, oblong or obovate, tips rather broad. Pappus absent.

Temperate regions; ca 200 species, 2 in India.

Literature. ISSAR, R.K. (1984) Achillea millefolium L. floristic variability of morphological characters. Ind. For. 104(2): 90-95. THOMSON, J. (1978). Yarrow, herbs of Achillea. Vascular 63(2): 13. Achillea millifolium.

KEY TO THE SPECIES

1a. Herbs; leaves 3-pinnatisect; heads 6 mm in diam.

2. Achillea millefolium

b. Undershrubs; leaves pectinately-pinnati-partite; heads 9 - 12 mm in diam.

1. Achillea alpina

List of Lower Taxa