Montane, subalpine.  Meadows.  Summer.
Robertson Pasture Trail, Abajo Mountains, Utah, August 16, 2011.

Erigeron subtrinervis is almost indistinguishable from Erigeron speciosus, and, in fact, Welsh (A Utah Flora) considers the plant shown on this page to be just a variety of E. speciosus.  John Kartesz, the ultimate authority for plant names on this web site, does consider them each at the species level. Weber (Colorado Flora) lists them as separate species but says, that E. subtrinervis "may simply be a race of" E. speciosus.

E. subtrinervis and E. speciosus are distinguished from each other by the hairs on their leaves.  Both have hairs along the margins of the leaves but only E. subtrinervis has hairs on the surface of its leaves. I looked at leaf surfaces for years before I found the plants shown on this page in the Abajo Mountains of Utah.

Erigeron subtrinervis (Showy Daisy)
Asteraceae (Sunflower Family)

Montane, subalpine.  Meadows.  Summer.
Robertson Pasture Trail, Abajo Mountains, Utah, August 16, 2011.

Erigeron subtrinervis (Showy Daisy)
Asteraceae (Sunflower Family)

Montane, subalpine.  Meadows.  Summer.
Robertson Pasture Trail, Abajo Mountains, Utah, August 16, 2011.

Both E. subtrinervis and E. speciosus have hairs along the leaf margins, but notice in this photograph, and even more clearly in the next photograph, that the surface of E. subtrinervis leaves (at least those at mid and upper stem level) has hairs.

Erigeron subtrinervis (Showy Daisy)
Asteraceae (Sunflower Family)

Montane, subalpine.  Meadows.  Summer.
Robertson Pasture Trail, Abajo Mountains, Utah, August 16, 2011.