Family - Asteraceae

Stems - To -2m tall, multiple from base, herbaceous, erect, branching above, hirsute, scabrous, carinate, from caudex.

Leaves - Alternate, sessile, pinnatifid to pinnately divided, +/-18cm long, scabrous, hirsute on midrib, with typically 3-11 lobes. Lobes entire to coarsely toothed, often divided again. Basal leaves drying before flowers.

Inflorescence - Single flower heads from long(+/-20cm) naked peduncles.

Involucre - Phyllaries spreading to reflexed, +/-9mm long, 2mm broad, subulate, antrorse strigose, scabrous.

Involucre.

Ray flowers - Flowers typically 10 in number. Ligule yellow, +/-6cm long, to 1.5cm broad, pubescent below and less so above, notched at apex, spreading to reflexed. Flowers sterile. Achene 2.5mm long, pubescent at apex. Pappus absent.

Disk flowers - Disk to 1.5cm in diameter, 2cm long, subglobose. Flowers fertile. Corolla tube to 2mm long, glabrous, 5-lobed. Lobes .2mm long, acute, deep brownish-purple, spreading. Stamens 5. Anthers deep brownish-purple, connate around style. Pollen yellow. Style exserted, bifurcate. Stigma deep brownish-purple. Achene slightly flattened, 3mm long, white, glabrous. Pappus absent. Receptacle 1cm long, 3mm broad, cylindrical. Chaff with purple margins, white below, green at apex, 5mm long, partially surrounding achene.

Flowering - May - September.

Habitat - Prairies, thickets, woodland edges, streambanks, railroads.

Origin - Native to U.S.

Other info. - This plant is common in the state and easy to ID in the field. The subglobose disk, long ray ligules, and pinnate leaves are good characteristics to look for.
I first photographed this plant by Buffalo Creek in Ripley County. Besides being a great place for plants, Buffalo Creek is loaded with crayfish:

Oronectes luteus

Oronectes punctinamus

I had tons of fun snorkeling and catching these crayfish in the crystal clear waters of Buffalo Creek. As tempted as I was, I did not eat any for dinner that evening.

Plant photographs taken off Hwy H., Shannon County, MO., 7-3-03 and 6-25-04.