Trichoptilium
Encyclopedia
Trichoptilium is a monotypic genus containing the single species Trichoptilium incisum, which is known by the common names yellowhead and yellowdome. This is a plant in the daisy family
which is native to the Mojave
and Sonoran Desert
s of the United States and Mexico.
with only disc florets. Each head is a hemispherical button about a centimeter in diameter. The fruit is bristly with pappus
.
Asteraceae
The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...
which is native to the Mojave
Mojave Desert
The Mojave Desert occupies a significant portion of southeastern California and smaller parts of central California, southern Nevada, southwestern Utah and northwestern Arizona, in the United States...
and Sonoran Desert
Sonoran Desert
The Sonoran Desert is a North American desert which straddles part of the United States-Mexico border and covers large parts of the U.S. states of Arizona and California and the northwest Mexican states of Sonora, Baja California, and Baja California Sur. It is one of the largest and hottest...
s of the United States and Mexico.
Description
Trichoptilium incisum sends up stems from a basal rosette of sharply-toothed leaves which are covered in curly hairs and oil glands. Atop each stem is a small rounded bright yellow flower headHead (botany)
The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae show lesser degrees of specialization....
with only disc florets. Each head is a hemispherical button about a centimeter in diameter. The fruit is bristly with pappus
Pappus (flower structure)
The pappus is the modified calyx, the part of an individual disk, ray or ligule floret surrounding the base of the corolla, in flower heads of the plant family Asteraceae. The pappus may be composed of bristles , awns, scales, or may be absent. In some species, the pappus is too small to see...
.