Mirabilis macfarlanei
Encyclopedia
Mirabilis macfarlanei is a rare species of flowering plant in the four o'clock family
Nyctaginaceae
Nyctaginaceae, the Four O'Clock Family, is a family of around 33 genera and 290 species of flowering plants, widely distributed in tropical and subtropical regions, with a few representatives in temperate regions...

 known by the common name MacFarlane's four o'clock. It is native to Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....

 and 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 only known from three river canyon
Canyon
A canyon or gorge is a deep ravine between cliffs often carved from the landscape by a river. Rivers have a natural tendency to reach a baseline elevation, which is the same elevation as the body of water it will eventually drain into. This forms a canyon. Most canyons were formed by a process of...

s. It faces a number of threats and is federally listed as a threatened species of the United States.

This plant is a perennial herb forming rounded clumps of stems up to a meter long. The plant grows from a taproot
Taproot
A taproot is an enlarged, somewhat straight to tapering plant root that grows vertically downward. It forms a center from which other roots sprout laterally.Plants with taproots are difficult to transplant...

 up to 3 inches (7.6 centimeters) wide and which may grow eight feet (2.4 meters) deep. It spreads via long 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...

s; what appear to be individual plants may be a number of clumps that arise from a single genetic individual. The purplish stems are lined with oval leaves up to 5 centimeters long by 5 wide. 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 3 to 7 flowers. The flower lacks a corolla of petals but has a calyx of magenta sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...

s 1.5 to 2.5 centimeters wide. The flowers are pollinated by solitary bees and the bumblebee
Bumblebee
A bumble bee is any member of the bee genus Bombus, in the family Apidae. There are over 250 known species, existing primarily in the Northern Hemisphere although they are common in New Zealand and in the Australian state of Tasmania.Bumble bees are social insects that are characterised by black...

 species Bombus fervidus
Bombus fervidus
Bombus fervidus is a species of bumblebee native to North America....

.

This plant grows in the canyons of the Snake
Snake River
The Snake is a major river of the greater Pacific Northwest in the United States. At long, it is the largest tributary of the Columbia River, the largest North American river that empties into the Pacific Ocean...

, Salmon
Salmon River (Idaho)
The Salmon River is located in Idaho in the northwestern United States. The Salmon is also known as The River of No Return. It flows for through central Idaho, draining and dropping more than between its headwaters, near Galena Summit above the Sawtooth Valley in the Sawtooth National...

, and Imnaha River
Imnaha River
The Imnaha River is a tributary of the Snake River in the U.S. state of Oregon. Flowing generally east near the headwaters and then north through Wallowa County, the entire river is designated Wild and Scenic...

s in western Idaho and far eastern Oregon. The sandy soil overlies talus
Scree
Scree, also called talus, is a term given to an accumulation of broken rock fragments at the base of crags, mountain cliffs, or valley shoulders. Landforms associated with these materials are sometimes called scree slopes or talus piles...

, and the often steep canyon slopes are easily eroded
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...

. The habitat is dry and relatively warm native 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...

 with some shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...

s. Common grass
Grass
Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...

es include bluebunch wheatgrass (Agropyron spicatum), sand dropseed
Sporobolus cryptandrus
Sporobolus cryptandrus is a species of grass known by the common name sand dropseed. It is native to North America, where it is widespread throughout southern Canada, most all of the United States, and northern Mexico.-Habitat:...

 (Sporobolus cryptandrus), and pine bluegrass
Poa secunda
Poa secunda is a widespread species of grass native to North America. It is highly resistant to drought conditions, and provides excellent fodder.-External links:**...

 (Poa secunda). Other plants in the habitat include yellow alyssum
Alyssum alyssoides
Alyssum alyssoides is a species of flowering plant in the mustard family known by several common names, including pale madwort and yellow alyssum...

 (Alyssum alyssoides), yarrow (Achillea millefolium), tufted evening primrose
Oenothera caespitosa
Oenothera caespitosa, known commonly as tufted evening primrose and fragrant evening primrose, is a perennial plant of the genus Oenothera native to much of western and central North America...

 (Oenothera caespitosa), smooth sumac
Rhus glabra
Rhus glabra is a species of sumac in the family Anacardiaceae, native to North America, from southern Quebec west to southern British Columbia in Canada, and south to northern Florida and Arizona in the United States and Tamaulipas in northeastern Mexico.One of the easiest shrubs to identify...

 (Rhus glabra), rubber rabbitbrush (Chrysothamnus nauseosus), and hackberry
Celtis reticulata
Celtis reticulata, with common names including Netleaf Hackberry, Western Hackberry, Douglas Hackberry, Netleaf Sugar Hackberry, Palo Blanco, Acibuche, is a small to medium size deciduous tree, native to western North America.-Prehistoric:Celtis reticulata was one of the species analyzed in a...

 (Celtis reticulata).

The plant was federally listed as an endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...

 in 1979. Conservation efforts and the discovery of additional populations led to a more optimistic outlook for the plant and its status was downlisted to threatened in 1996. By 2000 there were eleven populations. Based on monitoring data collected on federal lands, the total population had neither increased nor decreased by 2008. It is difficult to count or estimate the number of plants because many clumps of stems can belong to one genetic individual.

This species faces a number of threats. Most all of the populations are on land that has been heavily grazed by domestic cattle and sheep, and trampling and predation by the animals can adversely affect the plant. Grazing still occurs in some parts of the plant's range, and it generally grows in steeper spots that have been less impacted by grazing. The area is also browsed by bighorn sheep
Bighorn Sheep
The bighorn sheep is a species of sheep in North America named for its large horns. These horns can weigh up to , while the sheep themselves weigh up to . Recent genetic testing indicates that there are three distinct subspecies of Ovis canadensis, one of which is endangered: Ovis canadensis sierrae...

, elk
Elk
The Elk is the large deer, also called Cervus canadensis or wapiti, of North America and eastern Asia.Elk may also refer to:Other antlered mammals:...

, deer, and mountain goat
Mountain goat
The Mountain Goat , also known as the Rocky Mountain Goat, is a large-hoofed mammal found only in North America. Despite its vernacular name, it is not a member of Capra, the genus of true goats...

s. The 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....

 is negatively impacted by 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, including cheat grass (Bromus tectorum), St. John's wort (Hypericum perforatum), field bindweed
Convolvulus arvensis
Convolvulus arvensis is a species of bindweed, native to Europe and Asia. It is a climbing or creeping herbaceous perennial plant growing to 0.5–2 m high. The leaves are spirally arranged, linear to arrowhead-shaped, 2–5 cm long and alternate, with a 1–3 cm petiole...

 (Convolvulus arvensis), Dalmatian toadflax
Linaria dalmatica
Linaria dalmatica is a herbaceous plant native to western Asia and southeastern Europe that has become a weed in other areas. Its common names include Balkan toadflax, broadleaf toadflax, and Dalmatian toadflax.- External Links :...

 (Linaria genistifolia ssp. dalmatica), and yellow starthistle (Centaurea solstitialis). The three-toed stem-boring weevil (Mecinus janthinus) has been released into four o'clock habitat that is infested with dalmatian toadflax to act as an agent of biological pest control
Biological pest control
Biological control of pests in agriculture is a method of controlling pests that relies on predation, parasitism, herbivory, or other natural mechanisms...

 against the weed. While the four o'clock generally survives wildfire
Wildfire
A wildfire is any uncontrolled fire in combustible vegetation that occurs in the countryside or a wilderness area. Other names such as brush fire, bushfire, forest fire, desert fire, grass fire, hill fire, squirrel fire, vegetation fire, veldfire, and wilkjjofire may be used to describe the same...

 due to its large underground rhizome, fires increase the number of non-native plants growing in the area. Insecticide
Insecticide
An insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...

s may damage populations of important pollinating
Pollinator
A pollinator is the biotic agent that moves pollen from the male anthers of a flower to the female stigma of a flower to accomplish fertilization or syngamy of the female gamete in the ovule of the flower by the male gamete from the pollen grain...

 insects. Off-road vehicle
Off-road vehicle
An off-road vehicle is considered to be any type of vehicle which is capable of driving on and off paved or gravel surface. It is generally characterized by having large tires with deep, open treads, a flexible suspension, or even caterpillar tracks...

s and trampling by hikers
Hiking
Hiking is an outdoor activity which consists of walking in natural environments, often in mountainous or other scenic terrain. People often hike on hiking trails. It is such a popular activity that there are numerous hiking organizations worldwide. The health benefits of different types of hiking...

 may damage plants. Herbicide
Herbicide
Herbicides, also commonly known as weedkillers, are pesticides used to kill unwanted plants. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often synthetic "imitations" of plant...

 spraying has damaged populations. Insects have been noted to feed on the plant, including spittlebugs
Froghopper
The froghoppers, or the superfamily Cercopoidea, are a group of Hemipteran insects, in the suborder Auchenorrhyncha. Traditionally, most of this superfamily was considered a single family, Cercopidae, but this family has been split into three separate families for many years now: the Aphrophoridae,...

 (Aprophora and Philaenus sp.) and the small moth
Moth
A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...

 Lithariapteryx abroniaeella.
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