Compass Plant

Description

Silphium laciniatum, commonly known as Compass Plant, is a native perennial forb (wildflower) that grows in prairies, glades, roadsides, railroad right-of-ways, and other open, disturbed habitats. According to some sources, this plant can live up to 100 years!

Long-tongued bees are the primary pollinators of the flowers, including bumblebees, Miner bees, large Leaf-Cutting bees, and others. Short-tongued Halictine bees and Syrphid flies also visit the flowers, but they are less effective at pollination. Occasionally, Sulfur butterflies and Monarchs may visit the flowers for nectar. Several species of insects are specialist feeders of Compass Plant. This includes the uncommon Okanagana balli (Prairie Cicada), whose grubs feed on the large taproot, while a Rynchites sp. (Silphium Beetle) and its larvae feed on the flower heads and stems. The larvae of Antistrophus rufus and Antistrophus minor (Gall Wasp spp.) feed within the stems, forming galls that are not visible from the outside. Nonetheless, they attract the hyperparasitic wasp Eurytoma lutea, whose larvae feed on these gall formers. Similarly, the larvae of Mordellistena aethiops (Tumbling Flower Beetle sp.) feed within the stems, while the adults may eat the flowers. The oligolectic aphid Iowana frisoni sucks the juices from the flowering stems.

This plant is quite palatable during the growing season.

This is a typical plant of black soil prairies in the tallgrass region. It often co-occurs with Andropogon gerardii (Big Bluestem). Other habitats include sand prairies, savannas, glades, and areas along railroads.  This plant recovers from occasional fires readily.

Watch videos about this plant:

Silphiums for Wildlife

Grazing Silphiums