Pyrrocoma carthamoides is a species of flowering plant in the family Asteraceae known by the common name largeflower goldenweed. It is native to western North America from British Columbia to northeastern California to Wyoming, where it is known from grassland, woodlands, forests, barren areas, and other habitat. It is a perennial herb growing from a taproot and producing one or more stems to about half a meter in maximum length, the stems reddish-green and leafy. The largest leaves are at the base of the stem, measuring up to 20 centimeters long, lance-shaped with spiny sawtoothed edges. Leaves higher on the stem are smaller and hairier. The inflorescence is a single flower head or a cluster of up to four. Each bell-shaped head is lined with phyllaries each up to 2 centimeters long. It has many yellow disc florets surrounded by a fringe of yellow ray florets up to 7 millimeters long; ray florets are occasionally absent. The fruit is an achene which may be well over a centimeter in length including its pappus.
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.
Senecio blochmaniae is an uncommon species of flowering plant in the aster family known by the common names dune ragwort and Blochman's ragwort. It is endemic to the Central Coast of California, where it is known only from the direct coastline of San Luis Obispo and Santa Barbara Counties. It grows in sand dunes and sandy areas on coastal floodplains. It is a subshrub producing several arching stems often well exceeding a meter tall from a thick taproot. The stems are covered in many leaves, which are linear in shape, thick, and measure up to 12 centimeters long. The lower leaves become dry and curl up. The flower heads are lined by about 13 green-tipped phyllaries. They contain many yellow disc florets and each has usually 8 narrow yellow ray florets about a centimeter long.
Senecio californicus is a species of flowering plant in the aster family known by the common name California ragwort.
Packera cana is a species of flowering plant in the aster family known by the common name woolly groundsel. It is native to western and central North America, where it can be found in a wide array of habitat types at all elevations from grassland to the alpine climates of mountain peaks.
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.
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 eurycephala is a species of flowering plant in the aster family known by the common name widehead groundsel. It is native to a section of the western United States encompassing southern Oregon, northern California, and northern Nevada. It can be found in dry habitat types, often in disturbed areas, and it favors serpentine soils.
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.
Senecio lyonii is an uncommon species of flowering plant in the aster family known by the common name island senecio. This island endemic is known only from Guadalupe Island off the coast of Baja California and two of the Channel Islands of California, Catalina and San Clemente Islands. It grows in the coastal sage scrub and chaparral of the islands' hills and canyons. It is a shrub or subshrub growing from a woody taproot and reaching top heights well over one meter. The leaves have blades up to 12 centimeters long which are divided deeply into many narrow lobes. The inflorescence is made up of many clusters of flower heads. Each head has narrow phyllaries usually tipped with black, yellow disc florets and a fringe of yellow ray florets each about a centimeter long.
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 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.
Senecio minimus, commonly known as toothed fireweed and coastal burnweed, is a species of plant in the sunflower family. It is native to Australia and New Zealand, and also naturalized on the Pacific Coast of the United States.
