Cup Plant

Order: Asterales
Family: Asteraceae
Genus: Silphium
Species: S. perfoliatum

Identifying Characteristics:

- This native perennial plant is about 4-10' tall and remains unbranched, except for the panicle of flowering stems near the apex.

- The central stem is thick, hairless, and four-sided.

- The large opposite leaves are up to 8" long and 5" across, which join together around the central stem to form a cup that can hold water, hence the name of the plant. These leaves are broadly lanceolate to cordate, coarsely toothed, and have a rough, sandpapery texture.

- The yellow composite flowers bloom during early to mid-summer for about 1-1½ months. Each sunflower-like composite flower is about 3-4" across, consisting of numerous yellow disk florets that are surrounded by 18-40 yellow or pale yellow ray florets.

Special Adaptations:

- The preference is full or partial sun, and moist loamy soil. This plant may drop some of its lower leaves in response to a drought. Sometimes, the leaves and buds of distressed plants turn brown, growth becomes stunted, and blossoms abort in response to disease or drought. Another problem is that Cup Plant may topple over during a rainstorm with strong winds, particularly while it is blooming, or situated on a slope.

- Typical habitats include moist black soil prairies, moist meadows near rivers, low-lying woodland edges and thickets, fens and seeps, lake borders, fence rows, and along ditches near railroads.

-Long-tongued bees, butterflies, and skippers are common visitors and the most important pollinators of the flowers. Some short-tongued bees, wasps, bee flies, and other kinds of flies also visit the flowers for pollen or nectar.