Flower Color: Bright blue-purple or lavender with yellow centers; heads with both ray and diskflorets; bracts surrounding flower heads linear with elongated tips spreading or curving outward; fruit is a cypsela with a pappus.
Flowering Season: March or April to July through October, responds to summer monsoon rainfall.
Elevation: 2,500 to 8,000 feet (762-2,438 m)
Habitat Preferences: Various habitats across a wide range, open areas; Rocky Mountains and Great Plains to lower and upper Sonoran Desert, pine forests, chaparral, Creosote (Larrea) communities, pinyon-juniper and grassy areas, fields, roadsides, streams, streambeds and disturbed areas.
Recorded Range: In the United States, Tansyleaf Tansyaster is found in the central and southwestern parts of the country. In Canada it is native to Alberta and in Mexico it is found in the central and northern portions.
Genus Information: In North America there are 18 species and 18 accepted taxa overall for genus. Worldwide, The Plant List includes 27 accepted species names and a further 18 scientific names of infraspecific rank for the genus.
The genus Machaeranthera was published by Christian Gottfried Daniel Nees von Esenbeck in 1832.
In the Southwestern United States: Arizona has 13 species of genus, California has 8 species, Nevada has 8 species, New Mexico has 14 species, Texas has 8 species, Utah has 8 species. Data approximate and subject to revision.
Comments: Like many asters in the United States, Tansyleaf Tansyaster is common in its preferred range. The “tansy” or “fern-like” leaves make it easy to identify among similar species. It is similar in appearance to other asters and most particularly similar to the closely related Hoary Tansyaster, Dieteria canescens.
Species of the genus Machaeranthera, are found primarily in the western parts of North America. They are commonly known as Tansyasters. The word Machaeranthera is Greek for sword-like anthers and the anthers are actually sword-shaped and sharp-pointed. The pinnately shaped leaves helps separate this genus from the similar Dieteria whose leaves are simple.