Senecio flaccidus var. flaccidus, Threadleaf Ragwort
Scientific Name: Senecio flaccidus var. flaccidus
Common Name: Threadleaf Ragwort
Also Called: Treadleaf Groundsel, (Spanish: Hierba Ceniza)
Family: Asteraceae, Sunflower Family
Synonyms: (Senecio douglasii ssp. longilobus, Senecio douglasii var. jamesii, Senecio douglasii var. longilobus, Senecio filifolius, Senecio longilobus)
Size: Up to 3 feet.
Growth Form: Forb/herb, subshrub; erect; woody near base; herbage usually tomentose with white hairs but with some glabrescent.
Leaves: Green; alternate; margins pinnatifid, linear to filiform segments, entire and revolute.
Flower Color: Yellow; showy, ray flowers usually 8 florets; slender yellow, disk flowers yellow or orange-yellow, numerous; clusters with few to many heads on branch tips; bracts or phyllaries subtending flower head campanulate, fruit is an achene.
Flowering Season: March to May or may flower year-round.
Elevation: 2,500 to 7,500 feet.
Habitat Preferences: Upper and lower desert, pinyon-juniper community, chaparral, mesas, slopes, dry washes, sandy or rocky soils and disturbed areas.
Recorded Range: In the central southern United States including; AZ, CO, KS, NM, OK, TX and UT. Also found in Baja California and northern Mexico.
U.S. Weed Information: No data available.
Invasive/Noxious Weed Information: No data available.
Wetland Indicator: No data available.
Threatened/Endangered Information: No data available.
Senecio flaccidus var. douglasii, Douglas' Ragwort,
Senecio flaccidus var. flaccidus, Threadleaf Ragwort (AZ) and
Senecio flaccidus var. monoensis, Smooth Threadleaf Ragwort (AZ).
Arizona varieties overlap.
Comments: Threadleaf Ragwort, variety "flaccidus"; is a common large subshrub similar in appearance to Smooth Threadleaf Ragwort, Senecio flaccidus var. monoensis, but may be differentiated in the field where varieties overlap by its silvery or canescent woolly appearance and comb-like pinnatifid leaves. Also see Lemmon's Ragwort, Senecio lemmonii.
The genus Senecio is known to contain alkaloids which may cause liver damage in livestock.