"Agoseris" is Greek for "goat Chicory".

Foothills, montane, subalpine. Meadows. Summer.
Navajo Lake Trail, July 6, 2004.
Fish Creek Trail, July 28, 2000.

The leaf shape is different, the flower color is different, but the resemblance to yellow Dandelions is unmistakable.  Agoseris aurantiaca is far less common than common Dandelions and occurs scattered rather than in large colonies. Look for it tucked into grasses and other wildflowers right at the side of the trail.

Agoseris aurantiaca was first collected for science by Thomas Drummond in the Canadian Rockies in the 1820s; it was named Troximon aurantiacum by William Hooker in his Flora Boreali-Americana in 1833.  It was renamed Agoseris aurantiaca by Edward Greene in 1891 and has endured quite a few other name changes since then.

"Aurantiaca" is Latin for "orange" but the flower color can vary from orange to the typical rusty orange to lavender to the rare pink.

Foothills, montane, subalpine, alpine.  Meadows.   Summer.
Colorado Trail above Roaring Fork, August 7, 2004.

Agoseris glauca is very similar to Agoseris aurantiaca, but it is a slightly larger plant in leaf, flower, and overall plant size. The quite visible difference is flower color.  Leaves in both species are very similar: long, strap-like, vertical, and frequently red/purple or with a red/purple mid-vein. Cronquist indicates that A. glauca and A. aurantiaca might hybridize.

The plant was first collected by Thomas Nuttall on the banks of the Missouri River in about 1811 and was named Troximon glaucum by Frederick Pursh in 1814 in his Flora Americae Septentrionalis.  It was renamed by Constantine Rafinesque to Agoseris glauca in 1833.  "Glauca" is Greek for "gray".

Foothills, montane, subalpine, alpine.  Meadows.   Summer.
Lizard Head Trail, August 31, 2004.

Arched, purple and green phyllaries hold in the seeds until they fully ripen and explode in the characteristic Dandelion puff-ball.

Foothills, montane, subalpine, alpine.  Meadows.   Summer.
Middle Calico Trail, August 9, 2004.

Foothills, montane, subalpine, alpine. Meadows, woodlands. Spring, summer.
Lower Stoner Mesa Trail, May 27, 2004.

Golden Dandelion blooms carpet high mountain meadows in early spring.  Dandelions continue to  bloom - but to a lesser degree - into the fall.

Intermountain Flora states that because Taraxacum hybridizes, has multiple chromosome structures, and reproduces sometimes by producing seeds even when not fertilized, the "taxonomy and nomenclature [of Taraxacum] are in a state of utter confusion.  Well over a thousand arcane microspecies have been described."

Linnaeus named this plant Leontodon taraxacum in 1753 and it received its present name in 1779 from George Heinrich Weber (1752-1828).

Foothills, montane, subalpine, alpine. Meadows, woodlands. Spring, summer.
Canyons of the Ancients National Monument, April 16, 2004.

Dandelions are an introduced Eurasian species that have become entrenched almost world-wide because of their excellent seed dispersal and ease of germination.  Their crowded head of ray flowers produces numerous seeds that germinate easily and quickly so the plant is often found in huge colonies.  Dandelion's low, wide basal leaves crowd out competing plants (and also are commonly used in salads).  

The species name, "officinale", refers to the acceptance of Dandelion roots as an "official" drug.  The common name is a condensation of the French "dent de lion" (also the Latin "Leontodon"), "lion’s tooth", referring to the teeth on the leaves.  

"Taraxacum" is, according to the on-line Botanical Dictionary, "a  medieval name traceable through Arabic to the Persian "talkh chakok", meaning 'bitter herb' "; Intermountain Flora states the "name [is] of doubtful origin, perhaps from the Greek tarassein, to stir up, referring to reputed medicinal qualities".

Foothills, montane, subalpine, alpine. Meadows, woodlands. Spring, summer.
Ryman Creek Trail, June 16, 2005.

Bring a small hand lens when you take walks and sit down to examine the intricacies of even the most common flowers. 

Foothills, montane, subalpine, alpine. Meadows, woodlands. Spring, summer.
Lower Stoner Mesa Trail, June 12, 2004.

Dandelion seed heads with their multitude of silvery white pappus hairs have a beauty --  and fun  --  of their own.