Semi-desert, foothills. Woodlands, openings. Spring, summer.
Canyonlands National Park, Confluence Trail, May 20, 2004;
Lower Cross Canyon, May 2, 2016; Near Sixshooter Peaks, Canyon Lands, Utah, November 15, 2021.

Growing to over five feet, putting out a long plume of yellow flowers, and swaying in the wind gets you attention.  Place yourself in rocks at the side of the trail and the show is yours. 

Stanleya pinnata flowers are a deep lemon yellow. They open from the bottom of the flowering stem upward over a period of many weeks, sometimes months.  The dried stems persist for a year or two. 

Stanleya pinnata thrives on selenium rich soils and as a result, crushed stems or leaves may have an unpleasant odor.

The young plants in the second photograph at left and the one immediately below show off the several leaf shapes of Stanleya pinnata: lower leaves are deeply cut into lobes or they may even be cut so deeply that they are pinnatifid or pinnate. Upper leaves are reduced in size and they also may have a new shape  --  linear, linear/lanceolate, or ovate.

The photograph immediately below shows just the basal leaves of a 4 inch diameter Stanleya pinnata. In very dry years, such as 2020 and 2021, Stanleya pinnata will only have a clump of basal leaves and flower stalks (visible at the top center of the photograph) will grow to only a few inches above the basal leaves.

Frederick Pursh was the first to name this plant, but he placed it in the Cleome genus, giving it the name of Cleome pinnata in 1814 from a species collected by John Bradbury (1768-1823) "in Upper Louisiana [Territory]".  "Pinnata" is Latin for "feathered", referring to the feather-like, dissected lower leaves.

From a specimen he collected near the Missouri River, Thomas Nuttall realized that the plant was not a Cleome and in his 1818 Genera of North American Plants (click the title to read) he designated a new genus, Stanleya (honoring British naturalist Lord Stanley, 13th Earl of Derby).  Nuttall considered this species "the most splendid plant in the natural order Cruciferae" and he named it Stanleya pinnatifida.  Nathaniel Britton (1859-1934) renamed the plant Stanleya pinnata in 1889.  It has had several dozen other names since Pursh and Nuttall.  (More biographical information about Stanley.)

Semi-desert, foothills. Woodlands, openings. Spring, summer.
Along the Colorado River, Utah, April 13, 2005.