Description: This native perennial plant is 3-8' tall; it branches occasionally in the upper half. The stems are light green, terete, and usually hairless. The alternate leaves are up to 12" long and 12" across, becoming gradually smaller as they ascend the stems. They spread outward from their stems on long petioles and have a tendency to droop. The typical leaf has 3-7 large lobes, smooth or coarsely dentate margins, and a dark green upper surface that is hairless or slightly hairy. The lobes are elliptical or lanceolate in shape; the terminal lobe of each leaf is often subdivided into 2 smaller lobes. The uppermost leaves on the flowering stalks are much smaller in size and lanceolate to broadly ovate in shape; they lack lobes. The upper stems terminate in either individual or elongated clusters of flowerheads. Each flowerhead spans about 2½–3" across; it has a daisy-like structure consisting of a globoid central cone that is surrounded by 6-12 yellow ray florets. The central cone is light green while immature, but it later becomes yellow and resembles a pincushion to some extent because of the tubular disk florets. The ray florets have a petal-like appearance and they droop downward from the cone. There are about 5 floral bracts surrounding the base of the flowerhead; these bracts are light green, hairless, and ovate to oblong-ovate in shape. The blooming period occurs from mid-summer to early fall and lasts about a month. Each disk floret is replaced by an oblongoid achene that has a crown of tiny blunt teeth at its apex. The root system is fibrous and rhizomatous. Vegetative colonies of plants are often formed from the long rhizomes.
Cultivation: The preference is partial sun, moist
conditions, and a fertile loamy soil. At a site that is too sunny and dry, the
leaves may droop excessively and wither away. Otherwise, this is an easy plant
to cultivate.
Range & Habitat:
Cutleaf Coneflower is widely distributed and occasional in most areas of
Illinois (see
Distribution
Map). Habitats include open floodplain forests, moist meadows in wooded
areas, woodland borders, moist thickets, sloughs in partially shaded areas,
calcareous seeps, and pastures. Occasionally, this species is grown in flower
gardens.
Faunal Associations: The
nectar and pollen of the flowerheads attract many kinds of insects, including
long-tongued bees, short-tongued bees, predatory wasps, butterflies, skippers,
moths, and various kinds of flies. Cutleaf Coneflower is a host plant for the
caterpillars of the butterfly Chlosyne nycteis (Silvery Checkerspot) and
some moths (Synchlora aerata, Eupithecia miserulata). The Common
Goldfinch eats the seeds to a limited extent. The foliage of Cutleaf Coneflower
may be somewhat poisonous to some mammalian herbivores.
Photographic
Location: A flower garden in Urbana, Illinois. This is the wild form
of Cutleaf Coneflower because the flowerheads have no more than 12 ray florets,
as revealed in the upper photograph.
Comments: This is a tall-growing wildflower with a
rather lanky appearance. A cultivar of this species, called 'Golden Glow' has
double flowerheads with more ray florets (greater than 12) than the wild form.
Cutleaf Coneflower is one of several Rudbeckia spp. with yellow
flowerheads. It has larger and more widely separated disk florets than these
other species, which provides the mature central cone of its flowerheads with a
slight pincushion appearance. The central cones of Cutleaf Coneflower are light
green to yellow (depending on their maturity), while the central cones of other
Rudbeckia spp. are dark brown to black (e.g., Rudbeckia hirta,
Rudbeckia triloba, & Rudbeckia fulgida) or grey to brown
(e.g., Rudbeckia pinnata). The leaves of Cutleaf Coneflower have 3-7
deep lobes, while the leaves of other Rudbeckia spp. have fewer lobes or
none. An exception is Rudbeckia pinnata (Yellow Coneflower), which has
leaves with as many lobes. However, the lobes on its leaves are more narrow
than those of Cutleaf Coneflower.