Streptanthus niger is an endangered species within the family Brassicaceae. Like other genus members, this herb has wavy petal margins with perimeter calluses that discourage larval herbivory. This plant is endemic to the Tiburon Peninsula of Northern California, and occurs at elevations below 150 m on serpentine grasslands. The common name for this species is Tiburon jewelflower or black jewelflower. This annual herb blooms in May and June and displays dark purple sepals. The etymology of this genus scientific name derives from the Greek word streptanthus, meaning twisted flower, with reference to the notable wavy margins of the petals. The species name niger relates to the color of the seeds being black, although an alternate account cites the dark color of the petals as the source of the appellation.
Gentiana setigera is a species of gentian known by the common name Mendocino gentian. It is native to southern Oregon and northern California where it grows in wet places in the California Coast Ranges. It grows in serpentine soils.
Holozonia is a North American genus of flowering plants in the family Asteraceae. It contains only one known species Holozonia filipes, which is known by the common name whitecrown. It is endemic to California.
Calochortus raichei is a rare species of flowering plant in the lily family known by the common name Cedars' fairy-lantern. It is endemic to Sonoma County, California, where it is known only from The Cedars, an unincorporated area outside Guerneville north of Cazadero, just west of Austin Creek State Recreation Area.
Harmonia doris-nilesiae is a species of flowering plant in the family Asteraceae known by the common names serpentine tarweed and Niles' madia.
Harmonia hallii is a species of flowering plant in the family Asteraceae known by the common names Hall's harmonia and Hall's madia.
Harmonia stebbinsii is a species of flowering plant in the family Asteraceae known by the common name Stebbins' tarweed, or Stebbins' madia. It is endemic to northern California, where it is limited to the Klamath Mountains and adjacent slopes of the North Coast Ranges. It is a member of the serpentine soils plant community in these mountains, found at elevations of 1100–1600 meters. It is a rare annual herb producing a bristly stem up to about 25 centimeters tall studded with black resin glands. Its bristly leaves grow up to about 2 centimeters long and are mostly gathered near the base of the plant. The inflorescence is an array of flower heads lined with hairy, glandular, purple-tipped phyllaries. The head has a few yellow ray florets several millimeters long and yellow disc florets. The fruit is an achene tipped with a pappus.
Microseris paludosa is a species of flowering plant in the aster family known by the common names marsh silverpuffs and marsh microseris. It is endemic to California, where it has a scattered distribution between southern Mendocino and northern San Luis Obispo Counties, mainly near the coast. Its habitat includes coastal scrub and grassland and coniferous forest.
Pyrrocoma uniflora is a species of flowering plant in the aster family known by the common name plantain goldenweed. It is native to western North America from central Canada to California to Colorado, where it grows in several types of habitat, including forest and meadows with alkali soils, such as those near hot springs. It is a perennial herb growing up to 40 centimeters tall, the stems reddish and usually with a thin to thick coating of woolly fibers. The lance-shaped, toothed leaves are usually woolly, the largest near the base of the plant reaching up to 12 centimeters in length. The inflorescence is a single flower head or a cluster of a few heads, each lined with woolly phyllaries. The head contains yellow disc and ray florets. The fruit is an achene which may be over a centimeter long including its long pappus.
Sedum oblanceolatum is a species of flowering plant in the family Crassulaceae known by the common names oblongleaf stonecrop and Applegate stonecrop. It is native to the Klamath Mountains of southwestern Oregon and far northern California, where it grows on many types of rocky substrate, such as serpentine soils and other ultramafics. It is a succulent plant forming basal rosettes of waxy leaves. The leaves are widely lance-shaped, widest near the distal end and narrowing to rounded or notched tips. Smaller leaves occur farther up the stem. The small inflorescence grows a few centimeters tall and bears up to 50 flowers in a flat-topped array. The flowers have cream or yellowish petals up to a centimeter long.
Packera ganderi is a rare species of flowering plant in the aster family known by the common name Gander's ragwort. It is endemic to southern California, where it is known from a few occurrences in San Diego and Riverside Counties.
Pleiacanthus is a monotypic genus of flowering plants in the aster family containing the single species Pleiacanthus spinosus, which is known by the common name thorn skeletonweed, or thorny skeletonweed. It is native to the western United States from Montana and Idaho to southern California and Arizona, where it grows in many types of mostly dry habitat from deserts to mountains. It is a spindly subshrub producing several slender stems up to 40 or 50 centimeters tall from a woody caudex. The stems divide many times into short, rigid branches which narrow to sharp thorn-tips. The plant is mostly hairless except for brownish woolly tufts at the base and below the basal leaves. The leaves are small and linear on the lower stem, and reduced to scale-like growths on the upper branches. Flower heads occur near the ends of the branches. Each has a cylindrical base wrapped in one layer of phyllaries. The head contains 3 to 5 ray florets, each with an elongated tube and a pale to bright pink ligule. The fruit is an achene tipped with a cluster of pappus bristles which are not plumelike as are those of the Stephanomeria species with which this plant was once classified.
Streptanthus batrachopus is a rare species of flowering plant in the mustard family known by the common name Mt. Tamalpais jewelflower. It is endemic to Marin County, California, where it is known only from Mt. Tamalpais and surrounding terrain. There are fewer than ten known occurrences.
Streptanthus insignis is an uncommon species of flowering plant in the mustard family known by the common names plumed jewelflower and San Benito jewelflower. It is endemic to California, where it is known only from the Inner Central Coast Ranges. It grows in grassland and chaparral habitat, usually on serpentine soils. It is an annual herb producing a hairy, bristly, branching stem up to about 60 centimeters long. The lance-shaped basal leaves are borne on short petioles. Leaves midway up the stem are longer, and those near the top are shorter. They sometimes clasp the stem at their bases. Flowers occur at intervals along the upper stem. The uppermost flowers are often sterile and different in form. Each fertile flower has a bell-shaped calyx of sepals which is purple or greenish-yellow depending on subspecies. The petals at the tip are purplish or yellowish, also depending on subspecies. The fruit is a flat, straight silique which may be over 11 centimeters long.
Arnica dealbata is a species of Californian plants in the tarweed tribe within the aster family
Deinandra bacigalupii is a rare species of flowering plant in the family Asteraceae, known by the common names Livermore tarplant and Livermore moonshine. It is endemic to Alameda County, California, where there are only about five known occurrences around Livermore. It grows in open areas with alkali soils, such as alkali sinks and meadows. This plant was previously included within Deinandra increscens ssp. increscens, but it was separated and elevated to species level in 1999.
Erigeron maniopotamicus is a rare species of flowering plant in the aster family known by the common name Mad River fleabane. It is endemic to northwestern California, where it is known from only four locations in Humboldt and Trinity Counties.
Heterotheca monarchensis is a rare species of flowering plant in the aster family known by the common names monarch goldenaster and sequoia false goldenaster. It is endemic to Fresno County, California, where it is known from only one location near Boyden Cave in the Kings River Canyon. It grows in the limestone cliffs of this Sierra Nevada river canyon, along with a few other rare local endemics. The plant was discovered in July, 1995, and described to science as a new species in 1996.
Solidago missouriensis is a species of flowering plant in the aster family known by the common names Missouri goldenrod and prairie goldenrod. It is native to North America, where it is widespread across much of Canada, the United States, and northern Mexico. It grows from British Columbia east to Manitoba, south as far as Sonora, Coahuila, Texas, and Mississippi.
Harmonia is a genus of plants in the family Asteraceae. All 5 known species are endemic to the Coast Ranges of northern and central California. All but H. nutans grow on serpentine soils.
