7. Helianthus maximilianii Schrad. (Maximilian sunflower)
Pl. 280 g, h;
Map 1194
Plants perennial
herbs, with relatively short-creeping, thick, branched rhizomes and often somewhat
succulent roots, often occurring as dense colonies of stems. Stems often
appearing somewhat clumped, 50–200(–250) cm long, moderately to densely
pubescent with more or less stiff, short, ascending, often pustular-based hairs
throughout, not glaucous. Leaves relatively numerous and well developed along
the stem (usually more than 30 nodes), mostly alternate, mostly
short-petiolate, often appearing arched. Blades of the stem leaves 4–30 cm
long, 0.5–5.5 cm wide, narrowly lanceolate to lanceolate or narrowly
elliptic-lanceolate (mostly 7–20 times as long as wide), folded longitudinally
along the midvein, tapered at the base, tapered to a sharply pointed tip, the
margins entire or less commonly with minute, widely spaced teeth, flat, the
surfaces moderately to more commonly densely roughened-pubescent with minute,
usually stout, loosely appressed, pustular-based hairs (usually appearing
grayish green), also with moderate to dense, sessile, yellow glands, with 1
main vein. Inflorescences of solitary terminal heads or small terminal
clusters, also usually with axillary single or clustered heads present from the
upper leaves, commonly appearing overall spicate or racemose, the heads short-
to long-stalked. Involucre 12–25 mm long, 15–28 mm in diameter, mostly extending
beyond the tips of the disc corollas, the bracts in 2 or 3 subequal series,
narrowly lanceolate to nearly linear, tapered to a sharply pointed, slender,
loosely ascending to more commonly spreading or recurved tip, the margins with
a dense fringe of short hairs, at least toward the base, the surfaces
moderately to densely roughened-hairy and often also with scattered, sessile,
yellow glands. Receptacle convex, the chaffy bracts 7–11 mm long, narrowly
oblong-triangular to nearly linear, angled or short-tapered to a sharply
pointed, green, minutely hairy tip, the outer surface also minutely hairy. Ray
florets 10–25, the corolla 2.5–4.0 cm long, glabrous but often with scattered,
sessile, yellow glands. Disc florets with the corolla 5–7 mm long, yellow throughout.
Pappus of 2 scales 3–4 mm long, these oblong-lanceolate, tapered abruptly to a
sharply pointed, often minutely awnlike tip. Fruits 3–4 mm long, narrowly
wedge-shaped, flattened but more or less 4-angled in cross-section, the surface
glabrous, often finely mottled with dark brown and lighter brown patches. 2n=34.
July–October.
Scattered nearly
throughout the state (most of the U.S. [except some western and southeastern
states]; Canada). Calcareous glades, ledges and tops of bluffs, upland prairies,
loess hill prairies, and savannas; also old fields, railroads, roadsides, and
open, disturbed areas.
Maximilian
sunflower is a strikingly beautiful plant that makes an excellent addition to
the wildflower garden where there is room for it to grow. In cultivation,
plants usually develop into large, dense clumps of many stems to 3 m tall,
increasing in diameter slowly each year. Steyermark (1963) noted that the form
usually observed in disturbed habitats in eastern Missouri is similar to a
cultivar developed in the St. Louis area with more numerous heads having longer
ray corollas. He considered the species native only from the western portion of
the Ozarks northward to the loess hills of northwestern Missouri. Today, it has
become difficult to assess the eastern edge of the species’ native distribution
as it has been collected more frequently away from roadsides in the eastern
half of the state. Gleason and Cronquist (1991) considered H. maximilianii
to occur natively at least as far eastward as Ohio.