996 



COMPOSITAE 



Senecio 



o ~3o 

 Map 2184 



Cacalia tuberosa Nutt. 



o "To 



Map 2185 



Senecio vulgaris L. 



9411. SENECIO [Tourn.] L. 



[Greenman. Monograph of the North and Central American species of 

 the genus Senecio-Part II. Ann. Missouri Bot. Gard. 2: 573-626. 1915; 3: 

 85-194. 1916.] 



Plants leafy to the top, the leaves gradually diminishing upward; leaf blades mostly 

 pinnately parted; annuals. 

 Heads discoid, the numerous bracteoles of the calyx black-tipped, the principal in- 



volucral bracts about 7 mm long, sometimes black-tipped 1. S. vulgaris. 



Heads radiate; involucres with few or no bracteoles, not black-tipped, the principal 



involucral bracts about 5 mm long 2. S. glabellus. 



Plants usually with many large basal leaves, the cauline few and much smaller; 

 perennials. 

 Leaves and stems more or less persistently tomentose; basal leaves petiolate, elliptic 

 to oblong-lanceolate, mostly 15-40 mm wide, crenate-dentate; cauline leaves 



deeply and irregularly pinnatifid 3. S. plattensis. 



Leaves and stems glabrous or essentially so at maturity. 



Basal leaves obovate, sometimes one or rarely all subrotund to oblong-elliptic, 

 usually glabrous, narrowed at the base, rarely some subcordate; plants usually 



of dry soil on slopes and banks 4. S. obovatus. 



Basal leaves rotund-ovate, oblong-ovate to oblong-lanceolate, cordate to narrowed 

 at the base, glabrous or glabrate; plants of a wet or moist habitat, rarely of 

 a dry, sandy soil. 

 Lower leaves and those of rosettes usually large, round-ovate, the principal 



ones deeply cordate at the base; plants usually of a wet habitat 



5. iS. aureus. 



Lower leaves ovate to oblong-lanceolate, shallowly cordate, subcordate or long- 

 narrowed at the base. 

 Basal leaves and those of rosettes usually subrotund or of an ovate type, 



subcordate or truncate at the base 5a. S. aureus var. gracilis. 



Basal leaves cuneate at the base 6. S. pauperculus var. Balsamitae. 



1. Senecio vulgaris L. Common Groundsel. Map 2185. I first found 

 this species in 1919 on private grounds in the northern part of Muncie, 

 Delaware County. In 1929 I found it to be well established in the west 

 part of Bluffton, Wells County. I revisited the area in 1935 and found 

 that it is spreading. Madge McKee found it in Goodland, Newton County. 



