Semi-desert. Sand, openings.  Summer.
Near Farmington, New Mexico, September 20, 2013.

This annual Stephanomeria grows from about 5 to 25 inches tall. (The Flora of North America indicates that the plant can grow to 6 feet! Intermountain Flora indicates that it grows to a maximum of about 3 feet. Welsh says 20 inches.) In the photograph at left the plant is 10 inches tall and shows the typical array of stiff stems from both this year and last. Lobed basal leaves are withered by flowering time and stem leaves (as shown below) are reduced to mere bract-like appendages. Wiry, sometimes glaucous stems, often are branched near the top.

This species was discovered for science by famed botanist, Thomas Nuttall, in 1834, and Nuttall named and described the species in 1841. "Exigua" is Latin for "short", probably referring to the stem leaves and/or the minute bracts at the base of the involucre (see below).

Semi-desert. Sand, openings.  Summer.
Near Farmington, New Mexico, September 20, 2013.

Stephanomeria exigua subspecies exigua (Whiteplume Wirelettuce)
Asteraceae (Sunflower Family)

Semi-desert. Sand, openings.  Summer.
Near Farmington, New Mexico, September 20, 2013.

Just above the top flowerhead in the photograph at left you can see the silvery white pappus hairs of by-gone flowers. The arrows in the photograph below show (from top to bottom):
the long and narrow green phyllaries,
the very small phyllary-like appendages ("calyculi"),
the very small stem leaves.

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Foothill canyons.  Rocks, openings. Summer.
Canyons of the Ancients National Monument, September 19, 2005 and
Road 4.2 near Gateway, Colorado, June 24, 2016.

Stephanomeria pauciflora has a very slender, nearly vertical mass of thin, green stems with scattered pink/purple/white flowers.  Last year's dried, almost white stems are usually present at the bottom of the new green growth. Look for Wirelettuce in the sandy crevices of rocky canyon areas. 

As noted above, Thomas Nuttall named this genus in 1841, but in 1827 John Torrey had named this species Prenanthes pauciflora from a specimen collected by Edwin James in the Rockies.  In 1909 Aven Nelson re-examined Prenanthes pauciflora and realized that it belonged in the genus that Nuttall had created.  Nelson renamed the species "Stephanomeria pauciflora". "Pauciflora" is Latin for "few flowers".

Foothill canyons.  Rocks, openings. Summer.
Canyons of the Ancients National Monument, September 19, 2005. 

Numerous tightly rolled, narrow buds open over many days. 

Foothill canyons.  Rocks, openings. Summer.
Road 4.2 near Gateway, Colorado, June 24, 2016.

The downward arrow in the right corner points to the caudex (the woody base of a herbaceous stem) that the FNA notes is one of the characteristics separating P. pauciflora from P. tenuifolia. The latter species has rhizomes.

The other two downward arrows point to two different leaf shapes.

The two horizontal arrows point to two withered leaves. Most leaves are usually withered at flowering time.

Foothill canyons.  Rocks, openings. Summer.
Canyons of the Ancients National Monument, September 19, 2005. 

Foothill canyons.  Rocks, openings. Summer.
Butler Wash, Utah, August 27, 2007 and Behind the Rocks Wilderness Study Area, Moab, Utah, October 26, 2012.

Weber indicates that S. tenuifolia is "+- divaricately branched [diverging at a sharp angle], forming hemispherical bush growths" and that certainly fits the specimens at left.  Bright white and thickly plumose pappus hairs of the faded flowers can be seen throughout the second photograph at left.

L. D. Gottlieb who wrote the treatment of Stephanomeria for the Flora of North America indicates, "Stephanomeria tenuifolia is distributed over an immense region and is the most widespread species of the genus. It shows remarkable variability in the form and dimensions of its stems and branches." It sometimes approaches S. pauciflora in its size, shape, and other morphological characteristics. Gottlieb says that "the species are sufficiently compatible that fully fertile segregants with variously intermediate morphologies could be expected where they hybridize in nature".

This species, as the one above, also had its days of misidentification.  It was first given the genus name Prenanthes or Ptiloria around 1830 by Torrey and Rafinesque and then renamed Stephanomeria in 1907 by Harvey Hall.

"Tenuifolia" is Latin for "slender" "leaves".

Foothill canyons.  Rocks, openings. Summer.
Butler Wash, Utah, August 27, 2007.

Range map © John Kartesz,
Floristic Synthesis of North America

State Color Key

Species present in state and native
Species present in state and exotic
Species not present in state

County Color Key

Species present and not rare
Species present and rare
Species extirpated (historic)
Species extinct
Species noxious
Species exotic and present
Native species, but adventive in state
Eradicated
Questionable presence

Range map for Stephanomeria exigua

Range map for Stephanomeria pauciflora  

Range map for Stephanomeria tenuifolia