Packera malmstenii 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 Podunk ragwort. It is endemic to Utah

Utah

Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...

 in the United States, where there about 19 occurrences in the southwestern part of the state.

This perennial herb is generally about 8 to 15 centimeters tall, growing from a branching rhizome

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...

. It produces one stem or a small cluster of stems and leaves with oval blades up to 2.5 centimeters long. There is one or more flower heads

Head (botany)

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

, each with 13 blue-green 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...

 about a centimeter in length. The head may contain ray florets, or these may be absent. Blooming occurs in July and August.

This plant occurs on the limestone

Limestone

Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

 of the Claron Formation in Utah. It can be found on the Markagunt

Markagunt Plateau

The Markagunt Plateau is an plateau located in southwestern Utah between Interstate 15 and U.S. Route 89. It is one of the plateaus that make up the High Plateaus Section of the Colorado Plateau. The plateau encompasses Cedar Breaks National Monument and is part of Cedar Mountain District of...

, Aquarius

Aquarius Plateau

The Aquarius Plateau is a physiographic region within Garfield and Wayne counties in south-central Utah. The plateau, an uplift on the much larger Colorado Plateau, is the highest in North America...

, and Paunsaugunt Plateau

Paunsaugunt Plateau

The Paunsaugunt Plateau is a dissected plateau, rising to an elevation of , in southwestern Utah in the United States. Located in northern Kane County and southwestern Garfield County, it is approximately wide, and extends southward from the Sevier Plateau approximately , terminating in the Pink...

s. It occurs within the bounds of the Dixie National Forest

Dixie National Forest

Dixie National Forest is a United States National Forest in Utah with headquarters in Cedar City. It occupies almost two million acres and stretches for about 170 miles across southern Utah. The largest national forest in Utah, it straddles the divide between the Great Basin and the Colorado River...

 and Cedar Breaks National Monument

Cedar Breaks National Monument

Cedar Breaks National Monument is a U.S. National Monument located in the U.S. state of Utah near Cedar City. Cedar Breaks is a natural amphitheater canyon, stretching across , with a depth of over . The elevation of the rim of the canyon is over above sea level.The eroded rock of the canyon is...

. There are few threats to its survival because it occurs in inaccessible, rugged habitat and on soils high in calcium carbonate

Calcium carbonate

Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...

, which are inhospitable to weed

Weed

A weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More specifically, the term is often used to...

s.