Xylorhiza tortifolia is a species of flowering plant in the family Asteraceae, known by the common names Mojave-aster and Mojave woodyaster. The plant forms a small shrub with glandular leaves. The flower rays can be lavender, light blue, or white. Some varieties are known.
Native to southwestern North America, the plant can be found in deserts and washes. The Havasupai found uses for its fragrance.
Xylorhiza tortifolia is a perennial herb or subshrub with branching, hairy, glandular stems that reach in height. The leaves are up to long and lance-shaped or narrow, with a spiny tip and spiny-toothed edges, usually with a surface of gray hairs.
At the end of a long peduncle sits the inflorescence, a solitary flower head about across. The head has a base with long, narrow phyllaries which may be over long. The head contains up to 60 or more lavender, pale blue, or white ray florets which may be over 3 cm long. The bloom period is March through June.
The fruit is an achene which may be over 1 cm long, including its pappus of bristles.
Desert species of this aster with a woody base were removed from Machaeranthera, where they were placed for decades. A similar species, X. wrightii (Big Bend aster), is native to the Chihuahuan Desert in western Texas and northern Mexico.
Xylorhiza means 'woody base'.
The flowering plant is native to the Mojave Desert, Sonoran Desert, and Great Basin Desert ecoregions of the southwestern United States, California, and northwestern Mexico.
It grows in arid canyons and bajadas/washes, from in elevation. Habitats it is found in include creosote bush scrub, saltbush scrub, and Joshua tree woodlands.
The Havasupai used the plant for incense and fragrance, with ground leaves carried in the clothes and used as perfume by men and women to counteract body odors.