dalla 
Eupatorium 
1. Receptacle conical; base of stem with prostrate 
superficial stolons; flowers blue-violet...........-+. BH. coelestinum 
1. Receptacle flat; base of stem without superficial 
stolons; flowers white to purple. 
2. Involucre cylindric, the outer phyllaries 
closely imbricated, purple to creamy white. 
(Also, leaves usually whorled in 3's to 5's, 
lanceolate to ovate). 
3. Inflorescence round-topped; lower leaf 
surfaces and upper stem with glutinous dots 
(sometimes absent in E. purpureum). 
4, Leaves palmately 3-veined; involucre and 
flowers purple. Expected (E. dubium). 
4. Leaves pinnately veined; involucre and 
flowers white to pale lavender. (Also, 
stem with dark purple nodes; fresh plant 
strongly’ vanilla-scented) 2. oes eli. wte'ees Ee purpureum 
3. Inflorescence flat-topped; lower leaf 
surfaces and upper stem not glutinous- 
dotted. (Also, stem deep purple or purple- 
spotted; florets 8-20). Expected 
(E. maculatum). 
2. Involucre lax, the outer phyllaries not closely 
imbricated, green. (Also, leaves alternate or 
opposite, whorled only in E. hyssopifolium, and 
then linear to narrowly lanceolate). 
5. Leaves sessile or nearly so. 
6. Heads with 10 to 40 flowers. 
7. Leaves perfoliate, lanceolate, acuminate... E. perfoliatum 
7. Leaves with truncate or round bases, ovate, 
acute to blunt. Expected (E. aromaticum). 
6. Heads with 5 to 7 flowers. 
8. Leaves broadly subtruncate, round or . 
cordate at base. Expected (E. album). 
8. Leaves tapering to base. 
