Erigeron hessii is a rare species of flowering plant in the aster family

Asteraceae

The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...

 known by the common name Hess' fleabane. It is endemic to New Mexico

New Mexico

New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...

 in the United States, where it is known from two locations in the Mogollon Mountains

Mogollon Mountains

The Mogollon Mountains or Mogollon Range are a mountain range east of the San Francisco River in Grant and Catron counties of southwestern New Mexico, between the communities of Reserve and Silver City. They extend roughly north-south for about 30 miles , and form part of the divide between the...

. It is found only in the Gila Wilderness

Gila Wilderness

Gila Wilderness was designated the world's first wilderness area on June 3, 1924. Along with Aldo Leopold Wilderness and Blue Range Wilderness, the wilderness is part of New Mexico's Gila National Forest. The wilderness is approximately from north to south and east to west...

.

This rhizomatous

Rhizome

In botany and dendrology, a rhizome is a characteristically horizontal stem of a plant that is usually found underground, often sending out roots and shoots from its nodes...

 perennial herb produces hairy stems a few centimeters tall. The leaves are somewhat lance-shaped and up to 5 to 7 centimeters long. The flower heads

Head (botany)

The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae show lesser degrees of specialization....

 are lined with hairy, glandular phyllaries

Bract

In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale. Bracts are often different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture...

 and contain many white or lavender ray florets each up to 1.3 centimeters long.

This plant grows in subalpine

Subalpine

The subalpine zone is the biotic zone immediately below tree line around the world. Species that occur in this zone depend on the location of the zone on the Earth, for example, Snow Gum in Australia, or Subalpine Larch, Mountain Hemlock and Subalpine Fir in western North America.Trees in the...

 forest and grassland habitat in crevices in rock outcrops. There are only two occurrences, both near Whitewater Baldy

Whitewater Baldy

Whitewater Baldy is the highest point of the Mogollon Mountains in the southwestern part of the US state of New Mexico. It is also the highest point in the entire southwest portion of New Mexico . It is located in Catron County in the Gila Wilderness, part of the Gila National Forest...

in the Mogollon Mountains. There are a few hundred plants in each of the two populations.