Achillea millefolium subsp. millefolium

Tilcayo Cats original · Plants · Sources and editorial assessment · Originals retention rule

Achillea millefolium subsp. millefolium is the nominate subspecies of yarrow, a perennial plant in the daisy family, Asteraceae. Kew accepts this subspecies and records a native range extending across temperate and subarctic Eurasia and Greenland, with introductions elsewhere. The botanical name Achillea albicaulis C.A.Mey. is included among its synonyms.

Appearance

The University of Udine's regional flora describes plants about thirty to eighty centimetres tall, growing from an underground rhizome with spreading shoots. The upright, hairy stems branch near the flower clusters. The leaves are finely divided, with larger leaves near the base and smaller ones along the stem.

The many small flower heads form broad, roughly flat-topped clusters. Each head contains tubular flowers and outer flowers with white or pink strap-shaped parts. The dry fruits are achenes.

FloraWeb emphasises the subspecies' variability. Its account describes the bracts surrounding each flower head as mainly green, sometimes with pale brown margins, contrasting them with the darker-edged bracts of Achillea sudetica.

Regional habitat

In the area covered by the Udine flora, this yarrow is common in mown meadows, including both nutrient-poor and fertilised grassland, especially on relatively dry ground. It also occurs in disturbed places. The account records flowering from May to November and occurrences from sea level to about 2,200 metres. These are regional observations, rather than a flowering calendar or altitude limit for the subspecies throughout its range.