Erigeron annuus (L.) Pers.
Family - Asteraceae
Stems - To 1.5m tall, hirsute
to sparse pubescent, simple or branching above, herbaceous, terete to ridged, from
fibrous roots.
Lower portion of stem.
Leaves - Alternate. Lowest
leaves petiolate, to +10cm long. Petioles winged, to +2cm long. Upper cauline
leaves sessile, non-clasping, lanceolate to linear-lanceolate, coarsely
toothed to entire, with ciliate margins, pubescent above and below, to
9cm long, +2cm broad, reduced above.
Inflorescence - Single flower
heads terminating axillary peduncles. Peduncles slightly expanded just
below flower head, hollow, pubescent(appressed).
Involucre - In single subequal
series or with outer series of tiny, scant bracts and single inner series.
Phyllaries -1mm broad, 5-6mm long, entire, short pubescent to pilose, attenuate.
Receptacle dome-shaped in cross section.
Involucre.
Ray flowers - Pistillate.
Ligules white to pinkish, linear, threadlike, +/-100, to 1cm long,
-1mm broad, glabrous.
Disk flowers - Disk to -1cm
broad. Corollas yellow, 2-3mm long, 5-lobed. Achenes pubescent. Pappus
of barbed capillary bristles to 2mm long and often with short outer row
of scales.
Flowering - April - November.
Habitat - Waste ground, pastures, prairies, disturbed sites, roadsides, railroads.
Origin - Native to U.S.
Other info. - This is one
of the most weedy flowers in Missouri. It can bloom at a height of 10cm
if mowed over or cut. The leaves have quite a bit of variation in the amount
of teeth on the margins and the overall shape.
Photographs taken in the Ozark Scenic Riverways, 6-3-03.
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