Isocoma acradenia
Encyclopedia
Isocoma acradenia is a species of flowering plant in the daisy family
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...

 known by the common name alkali goldenbush. It is native to the southwestern United States and Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...

, where it grows in arid, sandy areas, particularly mineral-rich areas such as alkali flats and gypsum
Gypsum
Gypsum is a very soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is found in alabaster, a decorative stone used in Ancient Egypt. It is the second softest mineral on the Mohs Hardness Scale...

 soils.(C.Michael Hogan. 2010) This is a bushy subshrub reaching maximum heights of slightly over a meter. It produces erect, branching stems which are a shiny pale yellowish white, aging to a yellow-gray. Along the tough, hard-surfaced stems are linear or oval-shaped glandular leaves 1 to 6 centimeters long, sometimes with stumpy teeth along the edges. They are gray-green and age to pale gray or tan. The inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...

s along the top parts of the stem branches are clusters of four or five flower heads
Head (botany)
The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae show lesser degrees of specialization....

.(Jepson. 1993) Each head is a capsule encased in bumpy, glandular greenish phyllaries
Bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale. Bracts are often different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture...

 bearing many golden yellow disc florets at its mouth. Each disc floret is somewhat cylindrical and protruding. The fruit is an achene
Achene
An achene is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate and indehiscent...

 a few millimeters long with a yellowish 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...

adding an additional few millimeters.

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