Petradoria pumila is a very common plant found in extensive colonies lining trails and roads and filling meadows.  It first attracts attention to itself in early summer with bright green, dense, six inch diameter clusters of vertical leaves.  Then, in mid-summer (when this photograph was taken), its four-to ten inch stems are topped with a mass of tiny, attractive, golden/yellow flowers. The base of the plant often has a whorl of gray dead leaves from the previous year’s growth. This whorl could be confused with the very similar whorl of Stenotus armerioides.  Petradoria pumila is also confused with Gutierrezia sarothrae but the latter usually blooms later in August and September and is taller, woody, bright yellow, in more rounded clusters with very narrow, short leaves.

"Petra" is from the Greek for "rock: and "doria," is, according to William Weber, "an old name for a Goldenrod".  "Pumila" is Latin for "dwarf".

A specimen of this plant was first collected for science by Thomas Nuttall "in open situations on shelving rocks" in the Rockies (Intermountain Flora).  Nuttall named the plant Chrysoma pumila in 1841 and Edwin Greene renamed it Petradoria pumila in 1895.  This is the only species in the Petradoria genus.

Foothills. Roadsides, woodlands, openings. Summer.
Dolores River Overlook, July 26, 2009.