1168 CAKDUACEAE 



24. Eupatorium Mohrii Greene. Similar to E. leucolepis in habit. Stems slightly 

 more coarsely pubescent : leaves spreading or the lower ones drooping ; blades 2-6 cm. long, 

 serrate, prominently 3-ribbed beneath : involucre 6-7 mm. high ; bracts densely pubescent, 

 the inner minutely awn-tipped : achenes 2.5 mm. long. 



In sandy soil, South Carolina to Florida and Louisiana. Summer and fall. 



25. Eupatorium album L. Dull green. Stems 3-9 dm. tall, rather harshly pubes- 

 cent : leaves opposite ; blades oblong to lanceolate, 3-10 cm. long, usually acute or acutish, 

 serrate, prominently nerved beneath : corymbs 5-15 cm. broad : heads numerous : in- 

 volucres narrow, 8-9 mm. high, about 5-flowered ; bracts subulate-lanceolate to linear, 

 acuminate, the inner with white or whitish scarious tips : corollas white : achenes 3 mm. 

 long, sometimes sparingly glandular. 



In sandy soil, New York to Florida and Louisiana. Summer and fall. 



26. Eupatorium petaloideum Britton. Bright green. Stems 3-7 dm. tall, rough 

 with rather rigid hairs : leaves mainly opposite ; blades oblong to lanceolate, 2-8 cm. long, 

 obtuse or acutish, bluntly serrate or crenate-serrate, except the entire cuneate base, often 

 pubescent on the nerves beneath : involucres trumpet-shaped, 9-10 mm. high ; bracts 

 various, the outer nearly linear, abruptly acute, the inner white, petal-like and conspicu- 

 ous, mucronate, spatulate : corollas white : achenes nearly 3 mm. long, almost glabrous. 



In dry pine lands, Florida. Summer and fall. 



27. Eupatorium verbenaefblium Michx. Finely pubescent. Stems 6-12 dm. tall, 

 branching above : leaves opposite, few ; blades ovate to lanceolate, 2-12 cm. long, acute or 

 rather obtuse, serrate, rounded or truncate at the base, sessile : heads in rather dense 

 cymules : involucres 4-5 mm. high ; bracts oblong-lanceolate to linear, acutish, canescent : 

 corollas white or nearly so : achenes 2 mm. long, sparingly glandular. [E. teucriifolium 

 Willd.] 



.In sandy soil, Massachusetts to Florida and Louisiana. Summer and fall. 



28. Eupatorium rotundifolium L. Tomentulose. Stems 3-12 dm. tall, corymbosely 

 branched above : leaves opposite ; blades suborbicular to orbicular-ovate, 2-4 cm. long, 

 obtuse or acutish, crenate or crenate-dentate, truncate or subcordate at the base, the lower 

 ones sometimes incised : involucres 5-6 mm. high ; bracts lanceolate to linear, acutish or 

 apiculate, scarious-margined, canescent: corollas white: achenes about 2.5 mm. long, 

 glandular. 



In pine lands, New York to Arkansas, south to Florida and Texas. Summer and fall. 



29. Eupatorium pub6scens Muhl. Canescent-tomentulose. Stems 3-15 dm. tall, 

 corymbosely branched above : leaves opposite ; blades ovate, 2-10 cm. long, acute, serrate 

 or incised-serrate, rounded or truncate at the base, sessile : involucres 5-6 mm. high ; 

 bracts lanceolate to linear, canescent, acute, scarious-margined : corollas white : achenes 

 2-2.5 mm. long, glandular. 



In sandy soil, Massachusetts to Florida and Alabama. Summer and fall. 



30. Eupatorium scabridum Ell. Canescent-tomentulose. Stems 4-12 dm. tall, 

 corymbosely branched above: leaves opposite; blades elliptic to ovate-elliptic, 2-8 cm. 

 long, acute, serrate or incised-serrate, except the cuneate base, sessile or nearly so : heads 

 numerous : involucres less than 4 mm. high ; bracts oblong-lanceolate to lanceolate, acute 

 or acuminate, canescent : corollas white : achenes 2 mm. long, quite glandular. 



In dry soil, South Carolina to Florida. Summer and fall. 



31. Eupatorium sessilifolium L. Tomentulose above. Stems 4-15 dm. tall, corym- 

 bosely branched above : leaves opposite, spreading ; blades broadly lanceolate to linear- 

 lanceolate, 8-20 cm. long, attenuate, serrate, except the rounded base and the slender 

 apex, sessile : heads numerous : involucres 4-^5 mm. high ; bracts ovate-oblong to oblong 

 or linear-oblong, obtuse, minutely pubescent, the inner ribbed : corollas white or pinkish : 

 achenes 3.5 mm. long. 



In rocky soil, Massachusetts to Illinois, south to Georgia and Alabama. Summer and fall. 



32. Eupatorium Chapmanii Small. Tomentose above. Stems 4-12 dm. tall, 

 corymbosely branched, sometimes extensively so : leaves opposite ; blades firm, oblong to 

 oblong-ovate, 2-10 cm. long, merely acute, crenate, glandular as well as tomentose be- 

 neath, sessile and partly clasping : heads numerous : involucres cylindric, 5 mm. high ; 

 bracts mainly linear, pubescent, rather acute : corollas white : achenes 2 mm. long. 



In sandy soil, Florida. Summer. 



33. Eupatorium cuneatum Engelm. Tomentose above. Stems 5-16 dm. tall, 

 corymbosely branched : leaves opposite or mainly so ; blades lanceolate or oblong-lanceo- 

 late, 1-2 dm. long or shorter near the top of the stem, acuminate, finely and evenly cren- 





