About Acamptopappus sphaerocephalus (Harv. & A.Gray) A.Gray
Acamptopappus sphaerocephalus, a species of flowering plant in the family Asteraceae, is commonly known by the common name rayless goldenhead. It is native to the southwestern United States, specifically found in southern California, southern Nevada, southern Utah, and Arizona. This species grows as a shrub or subshrub, producing an upright, branching stem covered in shreddy whitish or gray bark. It reaches a maximum height close to one meter, though most individuals grow to between 20 and 40 centimeters tall. Its gray-green leaves are linear or lance-shaped, arranged alternately, and sometimes grow in small clusters. Leaves can be hairless or covered in small, rough hairs. The inflorescence is either a solitary flower head or a small cluster of flower heads. Each flower head is hemispherical or spherical in shape, bearing yellow disc florets and no ray florets. The fruit produced is an achene tipped with thick scales and bristles. This plant grows in the deserts of the southwestern United States, particularly the Mojave Desert, and is also found in the southern Great Basin and the northern Sonoran Desert. It grows in desert washes, plains, mesas, and ridges, and is a member of multiple plant communities including pinyon-juniper woodlands, mesquite, creosote, and grassy shrubsteppe. It may be associated with the following plant species: catclaw acacia (Acacia greggii), California juniper (Juniperus californica), scrub oak (Quercus turbinella), Joshua tree (Yucca brevifolia), California buckwheat (Eriogonum fasciculatum), golden cholla (Opuntia echinocarpa), and Mojave yucca (Yucca schidigera).
