Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

Home to the plants of the Sonoran, Chihuahuan and Mojave Deserts

Cirsium ochrocentrum, Yellowspine Thistle

Senecio flaccidus var. monoensis, Smooth Threadleaf Ragwort

Senecio flaccidus var. monoensis, Smooth Threadleaf Ragwort, Southwest Desert Flora Senecio flaccidus var. monoensis, Smooth Threadleaf Ragwort, Southwest Desert Flora Senecio flaccidus var. monoensis, Smooth Threadleaf Ragwort, Southwest Desert Flora   Senecio flaccidus var. monoensis, Smooth Threadleaf Ragwort, Southwest Desert Flora Senecio flaccidus var. monoensis, Smooth Threadleaf Ragwort, Southwest Desert Flora   Senecio flaccidus var. monoensis, Smooth Threadleaf Ragwort, Southwest Desert Flora

Scientific Name: Senecio flaccidus var. monoensis
Common Name: Smooth Threadleaf Ragwort
Also Called: Green Groundsel, Mono Ragwort, Sand Wash Groundsel and Shrubby Butterweed
Family: Asteraceae, Sunflower Family
Synonyms: (Senecio filicifolius, Senecio lathyroides, Senecio douglasii, Senecio douglasii var. monoensis, Senecio monoensis, Senecio pectinatus)
Status: Native
Duration: Perennial
Size: Up to 3 feet.
Growth Form: Forb/herb, subshrub woody base, herbaceous above, mostly glabrous, slender branches.
Leaves: Green; alternate, glabrous; margins entire, revolute, pinnately divided into narrow thread-like (filiform) segments; leaves up to 4 inches resemble a hair comb.
Flower Color: Yellow; showy, ray flowers 8 to 13; 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: 1,000 to 6,000 feet.
Habitat Preferences: Upper and lower desert, pinyon-juniper community, chaparral, mesas, slopes, canyons, dry washes, sandy or rocky soils.
Recorded Range: Native to southwestern United States from California to as far east as Texas in AZ, CA, NM, NV, TX, UT, also in Baja California and northern and central Mexico. It is found throughout Arizona.

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.

Genus Information: 69 species in Senecio throughout all of North America. 13 species in Arizona. 3 varieties for Senecio flaccidus, 2 in Arizona:
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: Smooth Threadleaf Ragwort, variety "monoensis" with its smooth, mostly glabrous features and comb-like pinnatifid leaves are key features that help to separate it from Smooth Threadleaf Ragwort, Senecio flaccidus var. monoensis where varieties overlap. Also see Lemmon's Ragwort, Senecio lemmonii.

The genus Senecio is known to contain alkaloids which may cause liver damage in livestock.

Date Profile Completed: 8/18/2012; Updated, 07/26/2015
References:
U.S. Dept. of Agriculture, Natural Resources Conservation Service on-line database
Arizona Flora, Kearney, Thomas H., Peebles, Robert H., 1960, University of California Press, Berkley and Los Angeles, as Senecio monoensis.
The Jepson Manual, Citation: http://ucjeps.berkeley.edu/interchange/I_treat_indexes.html Sat Aug 18 10:34:30 2012
Theodore M. Barkley, FNA | Family List | FNA Vol. 20 | Asteraceae | Senecio, Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 16+ vols. New York and Oxford. (accessed 08/18/2012)
SEINet for synonyms, scientific names and recorded geographic locations, http://swbiodiversity.org/seinet/