Pale-flowered leaf cup is named for the leafy appendages that wrap around the stem at the bases of the opposite leaves. A member of the sunflower family, leaf cup has about 8 white ray florets surrounding yellow disk florets.
Leaf cup is an upright perennial that can grow to almost 6 feet tall, with gland-tipped or sticky hairs toward the stem tips; the lower leaves are remarkably large and pinnately lobed.
The leaves leaves are opposite, bluish green, and very soft; they have short stalks or are stalkless. The lower leaves are largest, with 3–5 toothed, pointed lobes in a pinnate (featherlike) configuration; the leaf stem bases often have short, rounded, leaflike appendages wrapping around the plant stem; the appendages at the bases of a pair of opposite leaves together form a "cup" around the node, giving this plant its common name. The upper leaves are smaller and often unlobed.
The flowerheads are single or few in open clusters. The ray florets are 4–7 (usually 8), white, short, with 3 lobes at the outer margin; the ray florets are pistillate (have ovaries that develop into seeds). The disk florets are pale yellow and staminate (sterile; producing only pollen, not seeds). Beneath the flowerhead, the outer series of involucral bracts are 2–4, long and narrow.
Blooms May–October.
The fruits are small, dark achenes (structurally similar to sunflower "seeds") that only develop from the petal-like ray florets, not from the disk florets; they are slightly flattened with 3 blunt angles.
Similar species: A few other Missouri plants can be mistaken for pale-flowered leaf cup, depending on whether you're looking only at the foliage and growth habit, or only at the flowerheads:
- Bearsfoot, or yellow-flowered or hairy leaf cup (Smallanthus uvedalia, also written S. uvedalius), is closely related and was formerly placed in genus Polymnia. Its tall, straight stems and opposite, lobed leaves are very similar, but the leaf blade tissue tapers noticeably down the leaf stem. The flowers are quite different: the ray florets are 7–13, yellow, and much larger (about 1 inch long); beneath the flowerhead, the involucral bracts are 4–6, ovate, leafy, and spreading. A native Missouri wildflower, it occurs in similar habitats, scattered mostly in the southeastern half of the state.
- Fringed quickweed, or shaggy soldier (Galinsoga quadriradiata), has flowerheads that look very similar, with usually 5 short, white ray florets that are 3-lobed, and yellow disk florets. It, however, is an annual plant; it is usually much shorter, only growing to a maximum of 3 feet tall (it can flower at only 4 inches in height); and its leaves are all unlobed, ovate, toothed, with short, spreading hairs along the margins. A hairy plant; the hairs at the upper stems are tipped with tiny dark glands. It's nonnative, introduced from Central and South America; it is widely scattered in Missouri, along river banks, gardens, railroads, roadsides, and other open, disturbed areas.
Height: to 5 or even 6 feet (can start flowering at 18 inches in height).
Scattered in the Ozark and Ozark Border divisions of southern and central Missouri. Also in some additional counties along the Mississippi and Missouri rivers.
Habitat and Conservation
Occurs in bottomland forests, moist upland forests in ravines, bases and ledges of bluffs, and banks of streams and rivers; also occurs along fencerows, pastures, railroads, and roadsides.
Typically seen growing in large colonies along stream terraces. It is also quite common in moist, shaded areas in loose rubble at the bases of steep, rocky slopes or bluffs.
Status
Native Missouri wildflower.
Human Connections
Pale-flowered leaf cup, and its vegetative lookalike relative bearsfoot, can be grown as unusual specimen plants, for their large size and oakleaf-like foliage. Pale-flowered leaf cup, with its small flowerheads, is less showy than bearsfoot, but they are both good pollinator plants.
The unusual "leaf cups" at the base of the leaves of this plant represent the countless variations in the plant world. Botanists are people who study plants in all their variety. This helps humans by increasing our knowledge of environmental issues, crop production, biochemicals, and much more.
Ecosystem Connections
A variety of pollinators visit the flowers, and the foliage and seeds are eaten by a variety of animals. Birds, especially, relish the plump seeds.
Pale-flowered leaf cup, and its vegetative lookalike relative bearsfoot, have long, tall, stiff stems that are frequently hollow. These hollow stems are important nesting or overwintering habitat for a variety of solitary bees, so don't cut them until spring.
