Genus - Calamagrostis
Achillea is commonly known as feather reed grass.The genus name is derived from the Greek words kalamos, meaning reed and, agrostis, meaning grass. There are about 260 species in the genus.
Culture - Grow in medium to damp soil and in sun to part sun. Tolerant of heavy clay soils but, does best in moist rich soils. Cut to the ground in late winter before new shoots appear. This will minimize fungal diseases.