Senecio flaccidus var. flaccidus

Threadleaf Groundsel - Senecio flaccidus var. flaccidus
Near Percha Box
East of Hillsboro, New Mexico, USA
August 2, 2015

On the 2nd of this month, Rebecca and I found this Threadleaf Groundsel, Senecio flaccidus var. flaccidus, in the Percha drainage just west of the Percha Box (east of Hillsboro).  It goes by a number of common names including Douglas Groundsel and Douglas Ragwort which recognize the famed botanist David Douglas.  Threadleaf Groundsel has several scientific synonyms including Senecio douglasii.  This species was first described by Christian Friedrich Lessing (1809 - 1862), an expert in the family Asteraceae in 1830.  He did most of his work in Siberia.

This species is generally found in “disturbed” and over-grazed areas.  In over-grazed areas this species presents a classic “Catch 22”, it holds the soil in place when there is little else to do that but cattlemen don’t like the plant because it contains several alkaloids - which could harm their cattle if eaten in large quantities.  One of Threadleaf Groundsel’s early scientific synonyms was S. longilobus, recognizing the fact that it contained the alkaloid longilobine.  In all likelihood, the plant is present only because everything else has been eaten.  In what is, I am sure, an unintended commentary on the state of American Rangelands the Plants of Texas Rangelands site notes that: “Threadleaf Groundsel is a common range plant in Colorado and Utah and south to Texas and Mexico.  It is common in the grassland areas of western Texas.”

In our area we are at about the top of its elevation tolerance (6,500’).  It is found at elevations as low as 2,000’, so this plant can grow in the foothill and lowland areas surrounding the Black Range.  The geographic range of this species within the United States is shown in the map to the right, it is also found south into Central Mexico (Hidalgo, Jalisco, Veracruz, etc.).  Light green means the species is native and not rare in the county depicted.

© Robert Barnes 2018-2023