Calochortus umpquaensis is a species of flowering plant in the lily family

Liliaceae

The Liliaceae, or the lily family, is a family of monocotyledons in the order Liliales. Plants in this family have linear leaves, mostly with parallel veins but with several having net venation , and flower arranged in threes. Several have bulbs, while others have rhizomes...

 known by the common name Umpqua Mariposa lily. It is endemic to Oregon

Oregon

Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...

 in the United States, where it is mainly limited to the region of the Klamath Mountains

Klamath Mountains

The Klamath Mountains, which include the Siskiyou, Marble, Scott, Trinity, Trinity Alps, Salmon, and northern Yolla-Bolly Mountains, are a rugged lightly populated mountain range in northwest California and southwest Oregon in the United States...

 on the Little River in Douglas County

Douglas County, Oregon

-National protected areas:* Crater Lake National Park * Rogue River-Siskiyou National Forest * Siuslaw National Forest * Umpqua National Forest * Willamette National Forest -Adjacent counties:* Lane County, Oregon -...

, in particular the Watson and Ace Williams Mountains. The flower has also been found at a single location in each of Josephine

Josephine County, Oregon

Josephine County is a county located in the U.S. state of Oregon. According to Oregon Geographic Names, the county is probably named after a stream in the area called Josephine Creek, which in turn is probably named after Virginia Josephine Rollins Ort. In 2010, its population was 82,713...

 and Jackson Counties

Jackson County, Oregon

-National protected areas:* Cascade–Siskiyou National Monument* Crater Lake National Park * Klamath National Forest * Rogue River-Siskiyou National Forest * Umpqua National Forest -Demographics:...

.

This plant was described to science in 1989 when an isolated population of what had been reported to be Calochortus howellii was shown to belong to a separate species. The stem is 20 to 30 centimeters tall and the inflorescence

Inflorescence

An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...

 contains one or more flowers. The bell-shaped flower has three hairy white or cream-colored petals, each with a bearded purple-black blotch at the base, measuring up to 3.5 centimeters in length. The fruit is a capsule up to 5.4 centimeters long.

This wildflower is always found on serpentine soil

Serpentine soil

A serpentine soil is derived from ultramafic rocks, in particular serpentinite, a rock formed by the hydration and metamorphic transformation of ultramafic rock from the Earth's mantle....

s in a number of habitat types, including coniferous forest and grassland

Grassland

Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...

, and the ecotone

Ecotone

An ecotone is a transition area between two biomes but different patches of the landscape, such as forest and grassland. It may be narrow or wide, and it may be local or regional...

s between them. The soils are high in nickel

Nickel

Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...

, cadmium

Cadmium

Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...

, magnesium

Magnesium

Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...

, and phosphorus

Phosphorus

Phosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidized state, as inorganic phosphate rocks...

. Associated plant species include Jeffrey pine (Pinus jeffreyi), incense cedar

Calocedrus decurrens

Calocedrus decurrens is a species of conifer native to western North America, with the bulk of the range in the United States, from central western Oregon through most of California and the extreme west of Nevada, and also a short distance into northwest Mexico in northern Baja California...

 (Calocedrus decurrens), Douglas-fir

Douglas-fir

Douglas-fir is one of the English common names for evergreen coniferous trees of the genus Pseudotsuga in the family Pinaceae. Other common names include Douglas tree, and Oregon pine. There are five species, two in western North America, one in Mexico, and two in eastern Asia...

 (Pseudotsuga menziesii), Hooker’s silene

Silene hookeri

Silene hookeri is a species of flowering plant in the pink family known by the common names Hooker's silene, Hooker's Indian pink, and Hooker's glandular campion...

 (Silene hookeri ssp. hookeri), showy tarweed

Madia elegans

Madia elegans is a species of flower in the daisy family. It is generally known as the common madia, but there are several subspecies known by various common names.-Range:...

 (Madia elegans var. densifolia), cismontane minuartia

Minuartia cismontana

Minuartia cismontana is a species of flowering plant in the pink family known by the common name cismontane minuartia. It is native to Oregon and northern and central California, where it occurs in woodland and chaparral habitat, often on serpentine soils. It is similar to Minuartia californica and M...

 (Minuartia cismontana) and Roemer’s fescue (Festuca roemeri).

Though rare in general, the plant can be locally abundant, with the population at Ace Williams Mountain containing 400,000 to 800,000 individuals.

Threats to this species include nickel mining, introduced species

Introduced species

An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...

 of plants, and poaching

Poaching

Poaching is the illegal taking of wild plants or animals contrary to local and international conservation and wildlife management laws. Violations of hunting laws and regulations are normally punishable by law and, collectively, such violations are known as poaching.It may be illegal and in...

. Logging

Logging

Logging is the cutting, skidding, on-site processing, and loading of trees or logs onto trucks.In forestry, the term logging is sometimes used in a narrow sense concerning the logistics of moving wood from the stump to somewhere outside the forest, usually a sawmill or a lumber yard...

 and grazing

Grazing

Grazing generally describes a type of feeding, in which a herbivore feeds on plants , and also on other multicellular autotrophs...

of cattle are threats, but these have been mitigated recently on federal lands.