Flora of Colorado

Astragalus anisus is a species of flowering plant in the legume family known by the common name Gunnison milkvetch. It is endemic to Colorado in the United States, where it is limited to the Gunnison Basin of Gunnison and Saguache Counties. This plant is a small perennial herb growing from a woody taproot. The caudex is clothed with the remains of previous seasons' leaves. The leaves are up to 7 centimeters long and are compound, made up of up to 15 leaflets. The herbage is coated in silvery hairs. The pinkish purple flowers occur in May and June. They are up to 2 centimeters long. They are

Sclerocactus glaucus is a rare species of cactus known by the common name Colorado hookless cactus. It is endemic to Colorado in the United States, where it is known only from the area between Grand Junction and Montrose. It is a federally listed threatened species. The description of this species formerly included plants now belonging to Sclerocactus brevispinus and Sclerocactus wetlandicus, two cacti endemic to Utah. When the second of the two species was separated in 1994, the name S. glaucus was applied only to plants found in Colorado; it made the common name Uinta Basin hookless cactus

Astragalus osterhoutii, or the Osterhout milkvetch or Kremmling milkvetch, is an endangered species of milkvetch, discovered and collected in 1905 at Sulfur Spring in Grand County Colorado by Colorado botanist George Everett Osterhout for which the plant was named. It is found in the U.S. state of Colorado, in a 13 kilometres (8.1 mi) radius near the town of Kremmling. The Osterhout milkvetch is a perennial dicot. It belongs to the pea family, Fabaceae, and is in the Astragalus L. genus. Conservation efforts are centered around maintaining the populations and habitat due to the limited

Astragalus microcymbus is a species of flowering plant in the legume family known by the common name skiff milkvetch. It is endemic to Colorado in the United States, where it is known from Gunnison County and the edge of Saguache County. It was discovered in 1945 by Rupert Barneby, a British botanist. Currently, skiff milkvetch is experiencing population declines and is listed as a Tier 1 species in the Rare Plant Addendum to the Colorado State Wildlife Action Plan.

Astragalus linifolius is a species of flowering plant in the legume family known by the common name Grand Junction milkvetch. It is endemic to Colorado in the United States, where it is only found on the Uncompahgre Plateau in Delta, Mesa, and Montrose Counties. There are 21 occurrences, mostly in the general vicinity of Grand Junction. This perennial herb grows up to 50 centimeters in height. In May and June it produces many white flowers with purple-tinged keels. The fruit is a red legume pod. It grows on adobe and sandstone in pinyon-juniper woodland and sagebrush habitat. This species is

Boechera gunnisoniana, or Gunnison's rockcress, is a perennial herb of the family Brassicaceae (the mustards). It grows on windswept ridges as well as on stoney hillsides in west-central Colorado. The plant has many slender, erect stems which may reach a height of 15 cm. Flowering time is from May to June. According to chromosome counts, this species is diploid (n=7 as in all Boechera species) which probably reproduces sexually.

Astragalus wetherillii is a species of flowering plant in the legume family known by the common name Wetherill's milkvetch. It is native to Colorado and Utah in the United States. This perennial herb grows from a taproot and a caudex which yields several stems. The stems are partly purplish or reddish in color and are finely hairy. The leaves are green, without the silvery hairs of some other Astragalus. Each leaf is up to 10 centimeters long and is made up of up to 15 leaflets. The flowers are white or lavender-tinted and roughly a centimeter long. The fruit is a legume pod with a single

Aquilegia saximontana, the alpine dwarf columbine, dwarf blue columbine, or alpine columbine, is a perennial plant that comes from the buttercup family.

Physaria congesta (syn. Lesquerella congesta) is a rare species of flowering plant in the mustard family known by the common name Dudley Bluffs bladderpod. It is endemic to western Colorado in the United States, where it is known only from seven occurrences in Rio Blanco County. It is federally listed as a threatened species. This is a petite perennial herb taking the form of a small, compact mound no more than about 2 centimeters tall. A short stem arises from a hairy caudex that remains buried in the soil. This is attached to a long, slender taproot. The leaves are linear or lance-shaped

Penstemon mensarum, commonly called Grand Mesa penstemon, is a perennial plant in the veronica family. It has a very limited range in western Colorado, but is also grown in gardens.

Penstemon degeneri is a species of flowering plant in the plantain family known by the common name Degener's beardtongue. It is endemic to Colorado in the United States, where it occurs in and around the Arkansas River Canyon in Fremont, Custer, and Chaffee Counties. This species is a perennial herb producing several stems up to 40 centimeters tall from a caudex. The lance-shaped basal leaves are up to 6 centimeters long. Leaves higher on the stem are narrower and have a fine coat of hairs. The inflorescence bears up to 10 tubular flowers in shades of blue and purple. The flower may be nearly

Ipomopsis polyantha is a rare species of flowering plant in the phlox family known by the common names Pagosa ipomopsis, Pagosa skyrocket and Archuleta County standing-cypress. It is endemic to Colorado in the United States, where it occurs only in the vicinity of Pagosa Springs in Archuleta County. It is threatened by the loss of its habitat to residential and commercial development. It was federally listed as an endangered species in 2011. This plant is a biennial herb that grows 30 to 60 cm (12 to 24 in) tall. The stem is coated in glandular hairs. The leaves are deeply divided into narrow

Eriogonum pelinophilum is a rare species of wild buckwheat known by the common name clay-loving wild buckwheat. It is endemic to the state of Colorado in the United States, where it is known from only two counties. The most recent estimates available suggest there are 12 occurrences in existence for a total of about 278,000 individual plants in Delta and Montrose Counties. At least 7 occurrences observed in the past have not been relocated but are not yet believed extirpated. This plant is federally listed as an endangered species of the United States.

Draba weberi is a species of flowering plant in the family Brassicaceae known by the common names Weber's whitlow-grass and Weber's draba. It is narrowly endemic to Summit and Park Counties, Colorado, where several populations were estimated to total to approximately 300 individuals as of 2012. D. weberi is principally threatened by alterations to its hydrologic environment, owing to its preference for wet, rocky streamside crevices. Draba weberi is a perennial herb which grows in small, dense tufts with pubescent stems 2 to 6 centimeters long. Flowering occurs from June to July, whereupon

Boechera oxylobula, common name Glenwood Springs rockcress, is a plant species referred to as Arabis demissa in many older publications. The species is endemic to Colorado. It is known only from Garfield, Gunnison, Hinsdale, Lake, Mineral, Park, and Saguache counties in the central part of the state. It is found in open, rocky locations such as cliff faces, rocky slopes, and gravelly soil in brush. Boechera oxylobula is a perennial herb with several stems arising from a basal rosette. Leaves are linear, up to 2.5 mm (0.1 inches) wide. Flowers are white to pale lavender, borne in a terminal

Physaria obcordata is a rare species of flowering plant in the family Brassicaceae known by the common name Dudley Bluffs twinpod. It is similar in appearance to the more common Piceance twinpod, but can be distinguished by looking at the leaves through a hand lens. The Piceance twinpod, Physaria acutifolia has stellate hairs when viewed through a hand lens while Physaria ocordata has markings that look like a satellite dish, or a circle with a dot in the middle. It is endemic to Colorado, where it is found only in the Piceance Basin in Rio Blanco County. It is threatened by the loss and

Physaria bellii is a species of flowering plant in the family Brassicaceae known by the common names Bell's twinpod and Front Range twinpod. It is endemic to Colorado in the United States. This perennial herb produces decumbent or prostrate stems from a caudex. The plant is covered in hairs, making it silvery. The basal leaves are toothed and the leaves along the stems are smooth on the edges. The inflorescence is a raceme of flowers with yellow petals and yellowish sepals. The fruit is a leathery pod reaching nearly a centimeter in length. Flowering occurs in May and June. This plant grows

Phacelia formosula is a rare species of flowering plant in the borage family known by the common name North Park phacelia. It is endemic to the state of Colorado in the United States, where it is known only from the North Park region in Jackson County. It is threatened by a number of human activities, such as motorcycle and off-road vehicle use in its habitat. It is a federally listed endangered species of the United States. This plant was first collected on August 6, 1918, near Walden, Colorado. It was placed on the US Endangered Species List on September 1, 1982. There are eight to eleven

Penstemon teucrioides, commonly known as grayleaf creeping penstemon, germander penstemon and germander beardtounge, is a perennial species of plant in the large and colorful Penstemon genus. It is a ground hugging plant that is native to just five counties in the mountains of Colorado. Though it has a very limited range it is widely grown in rock gardens.

Penstemon penlandii is a rare species of flowering plant in the plantain family known by the common names Penland penstemon and Penland beardtongue. It is endemic to Colorado, United States, where it is known only from a strip of land of approximately twelve square kilometers (4.6 sq mi) in central Grand County. It is a federally listed endangered species of the United States. The first recorded observances of P. penlandii were in the 1980s during surveys for Osterhout milkvetch, another rare local endemic. The two plants are found only in Middle Park, a valley with seleniferous badlands that

Penstemon harringtonii, commonly known as Harrington's penstemon and Harrington's beardtongue, is a species of perennial flowering plant in the genus Penstemon in the family Plantaginaceae. P. harringtonii is narrowly endemic to northwestern and north-central Colorado in the United States. It generally populates sandy soil in the arid sagebrush steppe environment. The plant blooms between June and July with pink, blue, and purple flowers. The species is named for the botanist Harold Harrington.

Penstemon hallii, commonly Hall's penstemon or Halls alpine penstemon, is an alpine plant that is native to just the Southern Rocky Mountains of Colorado. It has showy flowers in shades of blue or purple the appear in summer.

Penstemon debilis, the Parachute penstemon or Parachute beardtongue, is one of the rarest plants in North America, found only 5 places in the world, all of them located on the Roan Plateau in Garfield County, of Western Colorado. The Denver Botanic Gardens has the Parachute penstemon on display with other native plants of the Roan Plateau. The name Parachute comes from the small town in Colorado, Parachute, Colorado, close to where the plant can be found. The plant is small and low to the ground. It has small green leaves and pale light-lavender flowers. It grows in steep slopes on shale,

Oenothera harringtonii is a species of flowering plant in the evening primrose family known by the common names Arkansas Valley evening primrose and Colorado Springs evening primrose. It is endemic to the state of Colorado in the United States. It is named for the botanist Harold Harrington. This species is part of the Oenothera caespitosa species complex. It is an annual, biennial, or short-lived perennial herb. It produces one or more stems from a basal rosette of leaves and a thick taproot. The stems reach up to 40 centimeters tall and are yellowish with reddish spots. The hairy leaves are

Mentzelia multicaulis, also known as manystem blazingstar, is a species of plant in the stickleaf family that is endemic to three counties in the state of Colorado.

Erythranthe gemmipara is a rare species of flowering plant in the family Phrymaceae, known by the common name Rocky Mountain monkeyflower. It is endemic to Colorado in the United States, where there are eight known occurrences. It was formerly known as Mimulus gemmiparus. This annual herb grows about 10 centimeters (3.9 inches) tall. Some of the leaves have propagules on their petioles called gemmae. When a leaf falls off the plant the gemma can generate a new plant; this is the mode of reproduction for this species, as flowers are rarely produced and they are sterile. The gemmae are probably

Cirsium perplexans is a species of flowering plant in the family Asteraceae known by the common names Rocky Mountain thistle and Adobe Hills thistle. It is endemic to Colorado in the United States, where it occurs in the Colorado and Gunnison River Valleys in the Rocky Mountains. This species is a biennial herb growing up to one meter tall from a taproot. The stems are coated thinly in webby fibers. The leaves are up to 30 centimeters long by 6 wide. They are sometimes unlobed but have toothed margins. The leaves have woolly fibers, especially on the undersides. The flower heads contain long

Ambrosia linearis is a species of flowering plant in the family Asteraceae known by the common names streaked bur ragweed, Colorado bursage, linear-leaf bursage, and plains ragweed. It is endemic to east-central part of the state of Colorado in the United States, where it occurs in Elbert, Pueblo, El Paso, Cheyenne, Crowley, Kiowa and Lincoln Counties. This species is a perennial herb or subshrub growing up to 40 centimeters or more in height. The leaves are mostly linear. Some are divided into lobes which are linear. They vary in length, measuring up to a few centimeters long. Like some

Thalictrum heliophilum is a species of flowering plant in the buttercup family known by the common names Cathedral Bluff meadow-rue and sun-loving meadow-rue. It is endemic to Colorado in the United States, where it is known from three counties. This perennial herb grows from rhizomes and fibrous roots. It produces one to three stems up to half a meter tall. The leaves are divided into leathery, waxy-textured leaflets each tipped with three teeth. The species is dioecious. The terminal inflorescence is a panicle of many flowers. The flower has four tiny sepals and no petals. The fruit is an

Physaria pulvinata is a flowering plant species in the family Brassicaceae known by the common name cushion bladderpod. It is a rare species endemic to the Mancos Shale Barrens of Dolores and San Miguel counties in southwest Colorado. Described by Steve O'Kane and James L. Reveal in 2006, this plant grows in dense mats with yellow flowers, gray stellate hairs, and ellipsoid fruits. This plant is considered a sensitive species and faces many threats including grazing, road construction, shale mining, invasive species and climate change.