244 American Midland Naturalist Monograph No. 7 



13. Stem sharply angled, at least below; leaves thick, 

 with only 1 principal vein, rugulose and 

 glabrous beneath, strongly scabrous above; 

 achenes glabrous; wet ground, local. Aug.- 

 Oct. Spreading Goldenrod ...S. patula Muhl. 



13. Stem terete; leaves thin, smooth (except the 

 margins), not rugulose; achenes pubescent. 

 14. Leaves with only one principal vein. 



15. Leaves lanceolate, entire, smooth, gla- 

 brous, 10-40 cm long; stem 0.5-2 m 

 tall; inflorescence dense, terminal; adv. 

 in Chicago, /. A. Steyerrnark in 1947; 



native along the e. coast of U.S 



S. scmpervirens L. 



15. Leaves elliptical, sharply serrate, pubes- 

 cent beneath along the veins; stem 30- 

 90 cm tall. 

 16. Stems lacking basal rosettes of leaves; 

 involucral bracts linear, acute; 

 borders of woods, or wooded 

 slopes or ridges, common through- 

 out 111. Aug.-Oct. Elm-leaved 



Goldenrod ...S. ulmifolia Muhl. 



16. Basal rosettes present; inxolucral 

 bracts obtuse; woods. Pine Hills, 

 Union Co., R. H. Mohlenbrock in 



1958 S. strigosa Small 



14. Leaves more or less plainly 3 -veined; in- 

 florescence a dense pyramidal panicle; rays 

 7-15; moist ground, common. Aug.-Oct. 

 [S. serotina Ait. not Retz. ; S. gigantea 



var. leiophylla Fern.] Late Goldenrod 



S. gigantea Ait. 



12. Branches of the panicle erect or ascending, the 

 heads not or scarcely secund. 

 17. Leaves mostly entire; heads 7-10 mm high; 

 panicle pyramidal; sandy or gravelly soil, or 

 in dry open woods. Aug.-Oct. Showy Golden- 

 rod [S. rigidiuscula (T. & G. ) Porter] 



- S. spcciosa Nutt. 



17. Leaves serrate; heads about 5 mm high; panicle 

 narrow, dense, wand-like; bogs, swamps, and 

 meadows, locally in the northern third of 111. 

 Aug.-Sept. Swamp Goldenrod [S. uniligu- 



lata (DC.) Porter; .S". neglecta T. & G.] 



S. uliginosa Nutt. 



1 1 . Branches of the inflorescence glabrous or nearly so. 

 18. Heads 4-5 mm high; plants strongly stoloniferous, 



