Senecio flaccidus explained

Senecio flaccidus, formerly recorded as Senecio douglasii (in honor of the botanist David Douglas), member of the daisy family and genus Senecio also known as threadleaf ragwort (and threadleaf groundsel, bush senecio, creek senecio, shrubby butterweed, comb butterweed, smooth threadleaf ragwort, Mono ragwort, Douglas ragwort, Douglas groundsel, sand wash groundsel, felty groundsel, old man, yerba cana, squawweed or cenicillo), is a native of the southwestern Great Plains of North America.^{[1] [2] [3] [4]}

Description

Threadleaf ragwort is a fast-growing, short-lived (3 to 6 years) bushy perennial shrub growing to 4inchesft6inchesin (ftin); common in gravelly washes, dry creek beds, along roads and trails and mostly away from the coast.^[2]

Leaves and Stems: Branched and bushy, Senecio flaccidus gets its common name from its white, threadlike, bent and matted, tomentose leaves; alternate and deeply pinnate, divided into five to nine narrow linear segments, glabrous, having no hairs or projections, gray-green above, 1inchesto4inchesin (toin) long. The principal leaves often have auxiliary clusters of smaller leaves.^[2] The stems are grooved and the branches are thin, herbaceous above and woody near the base.^{[1] [2]}

Flowers: Showy flowering heads of yellow ray flowers, 3inches–4inchesin (–in) across; eight to thirteen sterile rays, purplish brown disk florets that produce the seeds.^{[2] [3]}

Seeds: Dicotyledon fruits; each a NaNinches long achene ribbed and hoary, covered with short white hairs.^{[1] [2] [3]}

Toxicity

Colonizing disturbed areas including over-grazed lands, Senecio flaccidus helps to achieve a quick ground cover and helps to stabilize the soil for longer-lived perennials but in this situation makes poor foraging for cattle and horses due to the alkaloids contained in the plant which cause liver disease when consumed in large quantities.^[4]

Also known as Senecio longilobus, one of the alkaloids found in this species is longilobine,^[5] as well as senecionine, seneciphylline, florosenine, otonecine-based florosenine, and retrorsine.^[4]

Distribution

Like many Senecio Senecio flaccidus likes disturbed habitats, this one preferring overgrazed rangelands, dried up stream beds and desert grasslands;^[4] at altitudes above 1800feet and below 6500feet.^[3]

Native

America

North-Central: Kansas, Oklahoma

Northwestern: Colorado

South-Central: New Mexico, Texas

Southwestern: Arizona, Utah

Northern Mexico: Chihuahua, Coahuila, Durango, San Luis Potosí, Sonora, Zacatecas

Central Mexico: Aguascalientes, Guanajuato, Hidalgo, Jalisco (n.e.), Veracruz

Current ^[4]

America

North-Central: Kansas, Oklahoma, Wyoming

Northwestern: Colorado

South-Central: New Mexico, Texas

Southwestern: Arizona, California, Nevada, Utah

Northern Mexico: Chihuahua, Coahuila, Durango, San Luis Potosí, Sonora, Zacatecas, Baja California

Central Mexico: Aguascalientes, Baja Norte, Guanajuato, Hidalgo, Jalisco (n.e.), Veracruz

Subspecies which are synonyms

• Senecio flaccidus Less. var. flaccidus
• Senecio douglasii DC. var. longilobus (Benth.) L.D. Benson
• Senecio douglasii DC. var. jamesii (Torr. & A. Gray) Ediger ex Correll & M.C. Johnst.
• Senecio douglasii DC. ssp. longilobus (Benth.) W.A. Weber
• Senecio flaccidus Less. var. monoensis (Greene) B. L. Turner & T. M. Barkley
• Senecio flaccidus Less. var. douglasii (DC.) B. L. Turner & T. M. Barkley
• Senecio flaccidus var. flaccidus

See also

• Pyrrolizidine

External links

• Web site: Senecio flaccidus . 2008-02-20 . Integrated Taxonomic Information System . Integrated Taxonomic Information System Organization (ITIS) . 20 December 2007. Integrated Taxonomic Information System on-line database.
• Web site: Senecio flaccidus . 2008-02-20 . Arizona Vascular Plant Herbarium . Southwest Environmental Information Network.
• Web site: Taxon Report – 7491 . 2008-02-20 . Calflora . Information on California plants for education, research and conservation . The Calflora Database.

Notes and References

1. Web site: Senecio flaccidus Less. var. flaccidus . 20 February 2008 . Oklahoma Biological Survey . 1999-09-20 . Scientific Name Index . University of Oklahoma.
2. Web site: Senecio flaccidus Less. var. douglasii (DC) B. Turner & T. Barkley . 20 February 2008 . Michael L. Charters . Wildflowers and Other Plants of Southern California.
3. Web site: Sand Wash Groundsel . 20 February 2008 . George DeLange . Audrey DeLange . Arizona Wild Flowers Wildflower Pictures And Photos.
4. Web site: Senecio flaccidus Less. . 20 February 2008 . James E. Nellessen . United States Fish and Wildlife Service.
5. Henderson FG, Harris PN, Chen KK . Liver injury following administration of alpha- and beta- longilobine . Proceedings of the Society for Experimental Biology and Medicine . 76 . 3 . 530–532 . March 1951 . 14844262. 14844262 . 10.3181/00379727-76-18545. 75269601 .