Barkleyanthus is a monotypic genus of flowering plants in the aster family, Asteraceae, containing the single species Barkleyanthus salicifolius, a plant formerly classified in the genus Senecio. It is native to North and Central America, where its distribution extends from the southwestern United States to El Salvador. Its common names include willow ragwort, willow groundsel, Barkley's-ragwort, and jarilla.
Senecio aphanactis, known by the common names chaparral ragwort, rayless ragwort, and California groundsel, is a species of flowering plant in the aster family.
Senecio aronicoides is a species of flowering plant in the aster family known by the common name rayless ragwort. It is native to Oregon and northern and central California, where it can be found in the woodlands and forests of mountains and foothills, often in relatively dry habitat. It is a biennial or perennial herb growing up to about 90 centimeters tall from a fleshy root attached to a buttonlike caudex. The plant is often slightly woolly or cobwebby in texture. The leaves have lance-shaped to oval blades measuring up to 20 centimeters long, the largest ones lower on the stem. The inflorescence is a corymb which is flat and spreading, often resembling an umbel. The flower heads are cups lined with black- or green-tipped phyllaries and filled with many gold disc florets. There are usually no ray florets but one or two occasionally emerge from a head. The fruit is a hairless achene tipped with a pappus of long, white bristles.
Packera bernardina is a rare species of flowering plant in the aster family known by the common name San Bernardino ragwort.
Packera bolanderi is a species of flowering plant in the aster family known by the common names Bolander's ragwort and seacoast ragwort. It is native to the west coast of the United States from Washington to northern California, where it grows in wet coastal forests and woodlands. There are two varieties of the species which differ slightly in morphology and habitat occupied; these varieties have been considered separate species by some authors. The var. bolanderi has thicker leaves, occurs farther south, and occupies more open types of habitat, than does var. harfordii. This plant in general is a perennial herb producing one to three stems up to half a meter tall. The basal leaves have blades up to 12 centimeters long which are divided into several lobes and borne on long, thin petioles. Leaves growing farther up the stem are smaller and have more lobes on their blades. The inflorescence contains several flower heads, each lined with dark green phyllaries. The head contains many golden yellow disc florets and generally either 8 or 13 yellow ray florets each over a centimeter long. The fruit is an achene tipped with a pappus of bristles.
Senecio californicus is a species of flowering plant in the aster family known by the common name California ragwort.
Senecio clarkianus is a species of flowering plant in the aster family known by the common name Clark's ragwort. It is endemic to the Sierra Nevada of California, where it grows in the moist meadows on the western slopes of the range. It is a perennial herb growing up to 1.2 meters tall from a caudex and fibrous root system. The solitary erect stem is lined evenly with leaves up to about 18 centimeters long, their blades deeply lobed or dissected into narrow, pointed segments. The herbage is hairy to woolly in texture. The inflorescence bears several flower heads which are lined with green-tipped phyllaries. They contain many yellow disc florets and each has usually 8 or 13 narrow yellow ray florets about a centimeter long, sometimes longer.
Packera clevelandii is an uncommon species of flowering plant in the aster family known by the common name Cleveland's ragwort. It is endemic to California, where it is known from only two small regions, a section of the North Coast Ranges around Napa County and a part of the Sierra Nevada foothills on the opposite side of the Sacramento Valley. The plant grows in shrubby chaparral on serpentine soils.
Senecio elegans is a species of flowering plant in the aster family known by the common names redpurple ragwort, purple groundsel, wild cineraria and purple ragwort.
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.
Senecio hydrophiloides is a species of flowering plant in the aster family known by the common names tall groundsel and sweet marsh ragwort. It is native to western North America from British Columbia and Alberta to northern California to Utah, where it grows in wet meadows and similar habitat. It is a biennial or perennial herb producing a single erect stem or a cluster of a few stems which may exceed one meter in maximum height. The plants are green to red in color and usually without hairs, but new growth can be woolly. The leaves are lance-shaped to oval with toothed edges, the blades up to 25 centimeters long and borne on long winged petioles. The leaves are firm and sometimes a bit fleshy. The inflorescence is a loose or dense cluster of up to 30 or more flower heads lined with black-tipped phyllaries. They contain many yellowish disc florets at the center and often have some yellow ray florets, though these are sometimes absent. Senecio Hydrophiloides can cause Dermatitis.
Senecio hydrophilus is a species of flowering plant in the aster family known by the common names water ragwort and alkali-marsh ragwort. It is native to western North America from British Columbia to California to Colorado, where it grows in swampy places such as marshes. It can grow in standing water, including alkaline and salty water. It is a biennial or perennial herb producing a single erect stem or a cluster of a few stems which may exceed one meter in maximum height, at times approaching two meters. The stem is hollow, waxy in texture, and often pale green in color, and it emerges from a small caudex. The thick leaves are lance-shaped to oval with smooth or toothed edges, the blades up to 20 centimeters long and borne on petioles. Smaller leaves occur farther up the stem. The inflorescence is one or more large, spreading clusters of many flower heads. They contain many yellowish disc florets at the center and sometimes have small yellow ray florets as well.
Senecio integerrimus is a species of flowering plant in the aster family known by the common names lambstongue ragwort and tall western groundsel. It is native to western and central North America, where it grows in grassland, forest, and other habitat. It is a biennial or perennial herb producing one or a few erect stems 20 to 70 centimeters tall from a caudex with fleshy shallow roots. The linear to lance-shaped or triangular leaves are primarily basal, with blades up to 25 cm (10 in) long. The herbage is slightly hairy to woolly or cobwebby. The inflorescence bears several flower heads in a cluster, the middle, terminal head often largest and held on a shorter peduncle, making the cluster look flat. The heads contain many disc florets and usually 8 or 13 ray florets which may be yellow to cream to white in color. Some heads lack ray florets.
Packera layneae, known by the common name Layne's ragwort and Layne's butterweed, is a rare species of flowering plant in the aster family.
Senecio mohavensis, known by the common name Mojave ragwort, is a species of flowering plant in the aster family.
Senecio pattersonensis is an uncommon species of flowering plant in the aster family known by the common names Mono ragwort. and Mount Patterson senecio.
Senecio serra is a species of flowering plant in the aster family known by the common names tall ragwort and sawtooth groundsel. It is native to the western United States, where it can be found in several types of habitat, including sagebrush and woodlands. It is a perennial herb producing a single erect stem or a cluster of stems from a branched, woody caudex. The plant can exceed two meters in height. It is hairless in texture, with young plants sometimes appearing fuzzy, and green to red-tinged in color. The leaves have lance-shaped blades up to 20 centimeters long borne on short petioles, the leaves occurring evenly all along the stems. The inflorescence is a spreading array of many flower heads, each lined with green- or black-tipped phyllaries. The heads contain yellow disc florets and 5 to 8 yellow ray florets each under a centimeter long.
Senecio spartioides is a species of flowering plant in the aster family known by the common name broom-like ragwort. It is native to the western United States as far east as the Dakotas and Texas, and northern Mexico. It can be found in dry, rocky, often disturbed areas in a number of habitat types. It is a subshrub which can exceed a meter in height, its arching stems growing from a woody-topped taproot. The leaves are linear in shape and up to 10 centimeters long. The leaves usually have smooth, unlobed edges, but slightly lobed leaves are seen at times. The leaves are evenly distributed along the stems, the ones low on the stems withering away early, giving the plant a naked appearance on the lower half while the top is still lush green and blooming. The inflorescences are spreading, flat-topped arrays of many cylindrical flower heads. The heads contain yellow disc florets and generally either 5 or 8 ray florets each about a centimeter long.
Senecio sylvaticus is a species of flowering plant in the aster family. It is variously known as the woodland ragwort, heath groundsel, or mountain common groundsel. It is native to Eurasia, and it can be found in other places, including western and eastern sections of North America, as an introduced species and an occasional roadside weed. It grows best in cool, wet areas. It is an annual herb producing a single erect stem up to 80 centimeters tall from a taproot. It is coated in short, curly hairs. The toothed, deeply lobed leaves are up to 12 centimeters long and borne on petioles. They are evenly distributed along the stem. The inflorescence is a wide, spreading array of many flower heads, each lined with green- or black-tipped phyllaries. The heads contain yellow disc florets and most have very tiny yellow ray florets as well.
Senecio ertterae is a species of flowering plant in the aster family known by the common name Ertter's ragwort. It is endemic to Oregon, United States.
