Senecio 



Compositae 



997 



50 



Map 2187 



Senecio plaltensis Nutl 



50 



Map 2188 



Senecio obovatus Muhl 



~lo 



Map 2189 



Senecio aureus L 



Thus year after year we add European weeds to our flora and make it 

 necessary to increase our efforts to grow wanted vegetables and ornamental 

 plants. 



Nat. of Eu. ; Newf . to Hudson Bay, Minn., and B. C, southw. to N. C. 

 and Ind. 



2. Senecio glabellus Poir. Butterweed. Map 2186. This plant was 

 not known to Schneck in 1876 in the Lower Wabash Valley, and in 1897 

 Blatchley reported it as scarce in Vigo County, but it was collected by 

 Clapp in 1838 at New Albany. Evidently it is migrating into the state 

 at a rapid pace. It is now a common to abundant weed in most of the 

 area shown on the map. It prefers cultivated and fallow ground. In the 

 springtime, fields not plowed, oatfields, and wheatfields are sometimes 

 yellow with it. 



N. C, Ind. to Mo. southw. to Fla. and Tex. 



3. Senecio plattensis Nutt. Map 2187. This species is infrequent to 

 rare in the area shown on the map. It is found in dry, sandy soil on open, 

 black and white oak ridges, in moist soil between ridges, and in sandy 

 prairie habitats. 



Sw. Ont. to Sask., southw. to La. and Tex. 



4. Senecio obovatus Muhl. (Senecio obovatus var. rotundus Britt. and 

 Senecio obovatus var. umbratilis Greenman.) Roundleaf Groundsel. 

 Map 2188. Infrequent probably throughout the state, although there are 

 no records from the northwestern counties. Where it is found, it is usually 

 common to abundant over small areas. Its preferred habitat is clayey or 

 rocky slopes and dry clayey banks along streams. It is also found in moist 

 soil in various habitats. 



The variety rotundus Britt. is a form with subrotund basal leaves. A 

 study of large colonies of this species convinces one of the futility of try- 

 ing to keep this variety separate from the typical form since both forms 

 may be found in the same colony. The colonies, however, are usually of 

 one form and the two forms are about equally distributed throughout the 



