W168 

 (2 leaves) 



GROUNDSELS, RAGWORTS, AND BUTTERWEEDS 



Sene'cio spp. 



The genus Senecio, species of which are known as groundsels, ragworts, and 

 butterweeds, belongs to the senecio tribe of the aster, or composite family 

 (Asteraceae, or Compositae) and probably comprises a larger number of 

 species about 2,600 valid species are known than any other genus of flower- 

 ing plants. 1 The genus is of world-wide distribution and, although the species 

 native to the United States are mostly herbs, many species in Australia, Central 

 and South America, and in Africa are climbing vines, shrubs or trees ; in New 

 Zealand some species are timberline trees. The name Senecio is derived from 

 the Latin scnex, an old man, and seems to refer to the numerous white hairs 

 (pappus) of the seeds (achenes) or, according to certain writers, to the hoari- 

 ness of the herbage of some of the better known Old World species. The com- 

 mon name, groundsel, which has been accepted by the American Joint Com- 

 mittee on Horticultural Nomenclature 2 for most of the horticultural species of 

 this genus, and which is undoubtedly the name most often applied to the 

 majority of our range species of Senecio, is an old English word whose signifi- 

 cance is said to be ground swallower, alluding to the luxuriant growth of 

 pome of the British species. Ragwort is a term best restricted to <S. jacobaea 

 and other species with dissected (ragged) leaves. The term "butterweed" 

 refers to the butter-colored flowers and, in range parlance, best applies to 

 certain palatable species, particularly 8. serra and /S. triantfularis. For the 

 sake of convenience the term "groundsel" is here used to indicate any species 

 of the genus Senecio. 



Species of Senecio are, as a rule, easily recognized by the character of the 

 bracts (involucre) around the flower heads and by the numerous, soft, white 

 hairs (pappus) which crown the seeds. The comparatively few main involucral 

 bracts are flat, occur in one row, and usually are reinforced at the base by 

 an additional row of very short bractlets. The flower heads (yellow in our 

 species) are, as a rule, comparatively small, mostly erect, and borne in more 

 or less flat-topped clusters, or are solitary in a few species. Petallike ray 

 flowers are present in most of the western species, but usually are not numer- 

 ous. The heads of a few native western, species are comparatively large and 

 nodding; some species lack ray flowers. 



Possibly 200 species of Senodo occur in this country. The genus is well 

 represented in all the Western States, the various species occurring from sea 

 level up to elevations of about 14,000 feet, under practically all conditions of 

 soil moisture from very dry to wet, and in a wide variety of soil types from 

 rocky gravels to fine clays. Some species prefer the shade; others the direct 

 sunlight. On the more moist sites species of Senecio frequently grow in patches 

 and form a fairly dense ground cover. Other species are abundant on moder- 

 ately dry sites, although they do not ordinarily form pure stands. On the 

 whole, Senecio ranks among the most common genera of range weeds, its 

 members occurring in greater or less abundance on practically all ranges. 



The great size and diversity of the genus Senecio is reflected in the wide 

 variation in economic value existing among its numerous range representatives. 

 There is much still to learn as to the forage worth or possible toxic proper- 

 ties of the individual species. Arrowleaf butterweed (S. triangularis) , Colum- 

 bia butterweed (S. oolumbianus) , and sawtooth butterweed (8. serra,), three 

 common range species treated separately in this handbook, are characteristic 

 of the better species and rate from fair to fairly good for cattle and horses 

 and from good to very good for sheep. Quite possibly many of the smooth, 

 succulent species of moist sites deserve similarly high palatability ratings. 

 Usually, the species found in moist sites are more succulent and palatable 

 than those of the drier sites. Many species of moderately dry to dry sites 



1 Dayton, W. A. KNOWLEDGE OF PROPERTIES AND USES OF GROUNDSELS INCREASING. 

 U. S. Dept. Agr., Forest Worker 9(2) : 16. 1933. 



"American Joint Committee on Horticultural Nomenclature. STANDARDIZED PLANT 

 NAMES. . . . Prepared by P. L. Olmsted, F. V. Coville, and H. P. Kelsey. 546 pp. 

 Salem, Mass. 1923. 



