T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Yarrow

Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Asterales
Family: Asteraceae
Genus: Achillea
Species: A. millefolium
Binomial name: Achillea millefolium
Common name: Yarrow

Common yarrow is a weedy species and can become invasive. It is an erect herbaceous perennial plant that produces one to several stems (0.2 to 1m tall) and has a rhizomatous growth form. Leaves are evenly distributed along the stem, with the leaves near the middle and bottom of the stem being the largest. The leaves alternate, 7-10cm / 3-4in long and 2-3cm / 1in broad, clasping the stem at the base,  pinnatifid, the segments very finely cut, giving the leaves a feathery appearance to which it owes its name (Millefolium meaning thousand-leaved).
The inflorescence has 4 to 9 phyllaries and contains ray and disk flowers which are white to pink. There are generally 3 to 8 ray flowers that are ovate to round. Disk flowers range from 15 to 40. The inflorescence is produced in a flat-topped cluster.

Photographed July




The "millefolium" used in the name because of the thousands of leaf segents.


^ Top

Previous page: Willow Weed (Persicaria maculosa)
Next page: Vervain (Verbena officinalis)