4. Verbascum thapsus L. (mullein, flannel plant)
Pl. 560 f, g;
Map 2609
Stems 30–230 cm
long, erect, circular in cross-section or slightly polygonal, unbranched or
occasionally few-branched toward the tip, densely woolly with branched (having
an axis) and stellate, nonglandular hairs. Leaves appearing grayish green or
light yellowish green (the green surfaces obscured by pubescence), those of the
basal rosettes 8–55 cm long, sessile or with a short, winged petiole, the blade
oblanceolate to obovate, the margins unlobed and entire or shallowly scalloped
to bluntly toothed; stem leaves progressively shorter toward the stem tip,
entire to finely scalloped or toothed, sessile, oblong-oblanceolate to
oblanceolate, the bases decurrent down the stems as a pair of wings, grading
fairly abruptly into the inflorescence bracts; leaf blades with the surfaces
densely woolly with branched (having an axis) and stellate, nonglandular hairs.
Inflorescences dense spikelike racemes (occasionally appearing paniculate in branched
plants), the flowers solitary or more commonly in small, irregular clusters at
the nodes, the flower stalks absent or to 4 mm long, densely woolly. Calyces
5–12 mm long, the lobes lanceolate to triangular-lanceolate, densely woolly.
Corollas 8–18 mm long, yellow, lacking reddish markings, the margins minutely
stellate-hairy. Stamens unequal, the upper 3 with the filaments and anthers
shorter, straight, the filaments densely bearded with yellow hairs; the lower 2
with the filaments and anthers longer, glabrous or sparsely hairy, the anthers
orange, those of the lower pair fused laterally to the filaments for most of
their length. Fruits 7–10 mm long, broadly ovoid, densely stellate-hairy. 2n=32,
36. May–September.
Introduced,
scattered to common nearly throughout the state (native of Europe, Asia;
introduced widely nearly throughout temperate North America and sporadically
farther south). Banks of streams and rivers, margins of ponds, lakes, marshes,
and oxbows, and disturbed portions of glades and upland prairies; also old
fields, pastures, fallow fields, farm yards, ditches, railroads, roadsides, and
open, disturbed areas.
Verbascum
thapsus plants are
avoided by grazing mammals and thus can become problem weeds in pastures. The
fuzzy, first-year rosettes are distinctive, as are the tall, stout, second-year
flowering stems. A rare, white-flowered mutant has been called f. candicans
House, but has not yet been recorded from Missouri.