Mentzelia leucophylla
Encyclopedia
Mentzelia leucophylla is a rare species of flowering plant in the Loasaceae
known by the common name Ash Meadows blazingstar. It is endemic to Nevada
in the United States, where it is known only from Nye County
. It is one of several rare plants to be found only in Ash Meadows
, an area with a unique desert
wetland
ecosystem
. It is threatened by the degradation of its habitat, and it is federally listed as a threatened species of the United States.
This is a biennial or perennial herb growing up to half a meter tall. The stem and herbage are coated in tiny white hairs, making them pale and velvety. The wide inflorescence
bears bright yellow flowers in May through September. The flowers open for a short time in the afternoon.
Ash Meadows is a stretch of desert floor with areas of wetland habitat kept moist by springs and seeps
originating from a supply of groundwater
. This water supports a variety of flora and fauna, including many rare and endemic taxa such as Ash Meadows milkvetch
(Astragalus phoenix) and Ash Meadows sunray
(Enceliopsis nudicaulis var. corrugata), which are found growing alongside the blazingstar. The substrate is fine-grained sand and clay crusted with salt and alkaline in pH
. The area is generally dominated by shadscale
(Atriplex confertifolia) and associated halophytic
vegetation.
For many decades the Ash Meadows area has been disturbed by a number of human activities, including peat
mining, construction of roads, real estate development, and agricultural
practices such as plowing, water diversion, and grazing. The pumping of groundwater
proved to be a serious threat, as it lowered the high water table
that supports the ecosystem.
Loasaceae
The Loasaceae is a family of 15-20 genera and about 200-260 species of flowering plants in the order Cornales, native to the Americas and Africa. The family comprises annual, biennial and perennial herbaceous plants, and a few shrubs and small trees.Genera...
known by the common name Ash Meadows blazingstar. It is endemic to Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...
in the United States, where it is known only from Nye County
Nye County, Nevada
-National protected areas:* Ash Meadows National Wildlife Refuge* Death Valley National Park * Humboldt-Toiyabe National Forest * Spring Mountains National Recreation Area -Demographics:...
. It is one of several rare plants to be found only in Ash Meadows
Ash Meadows National Wildlife Refuge
The Ash Meadows National Wildlife Refuge is a protected wildlife refuge, administered by the U.S. Fish and Wildlife Service, located west-northwest of Las Vegas, Nevada, in southern Nye County...
, an area with a unique desert
Desert
A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...
wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....
ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
. It is threatened by the degradation of its habitat, and it is federally listed as a threatened species of the United States.
This is a biennial or perennial herb growing up to half a meter tall. The stem and herbage are coated in tiny white hairs, making them pale and velvety. The wide 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...
bears bright yellow flowers in May through September. The flowers open for a short time in the afternoon.
Ash Meadows is a stretch of desert floor with areas of wetland habitat kept moist by springs and seeps
Seep (hydrology)
A Seep is a moist or wet place where water, usually groundwater, reaches the earth's surface from an underground aquifer.-Description:Seeps are usually not of sufficient volume to be flowing beyond their above-ground location. They are part of the limnology-geomorphology system...
originating from a supply of groundwater
Groundwater
Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock...
. This water supports a variety of flora and fauna, including many rare and endemic taxa such as Ash Meadows milkvetch
Astragalus phoenix
Astragalus phoenix is a rare species of milkvetch known by the common name Ash Meadows milkvetch. It is endemic to Ash Meadows, a desert oasis and wildlife refuge in Nye County, Nevada, near the California border. It is one of several rare plants and animals endemic to the area...
(Astragalus phoenix) and Ash Meadows sunray
Enceliopsis nudicaulis
Enceliopsis nudicaulis is a species of flowering plant in the daisy family known by the common name nakedstem sunray, or naked-stemmed daisy.-Distribution:...
(Enceliopsis nudicaulis var. corrugata), which are found growing alongside the blazingstar. The substrate is fine-grained sand and clay crusted with salt and alkaline in pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
. The area is generally dominated by shadscale
Atriplex confertifolia
Atriplex confertifolia is a species of evergreen shrub in the Chenopodiaceae family, which is native to the western United States.-Habitat:Shadscale is a common, often dominant, shrub in the lowest and driest areas of the Great Basin...
(Atriplex confertifolia) and associated halophytic
Halophyte
A halophyte is a plant that grows where it is affected by salinity in the root area or by salt spray, such as in saline semi-deserts, mangrove swamps, marshes and sloughs, and seashores. An example of a halophyte is the salt marsh grass Spartina alterniflora . Relatively few plant species are...
vegetation.
For many decades the Ash Meadows area has been disturbed by a number of human activities, including peat
Peat
Peat is an accumulation of partially decayed vegetation matter or histosol. Peat forms in wetland bogs, moors, muskegs, pocosins, mires, and peat swamp forests. Peat is harvested as an important source of fuel in certain parts of the world...
mining, construction of roads, real estate development, and agricultural
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
practices such as plowing, water diversion, and grazing. The pumping of groundwater
Groundwater
Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock...
proved to be a serious threat, as it lowered the high water table
Water table
The water table is the level at which the submarine pressure is far from atmospheric pressure. It may be conveniently visualized as the 'surface' of the subsurface materials that are saturated with groundwater in a given vicinity. However, saturated conditions may extend above the water table as...
that supports the ecosystem.