Tickseed coreopsis is a showy, prominent glade perennial that usually has several stems. The flowerheads are few but large, about 2 inches across, the ray florets typically broad, uniformly yellow, the ends sharply, jaggedly toothed. Blooms April–June. Leaves are narrow, undivided, mostly at the lower half of the stems. Fruits are seeds (achenes) that somewhat resemble ticks; the name “coreopsis” is derived from Greek and means “resembling a bug.”
Similar species: There are 6 species of Coreopsis recorded for Missouri. We also have 11 species in the genus Bidens (beggar’s ticks), which can be confused with Coreopsis species.
Height: to 2 feet.
Scattered mostly in the Ozarks and north to the Missouri River. Cultivated, and escapes from cultivation, statewide.
Habitat and Conservation
Grows natively in rocky prairies, glades, tops of bluffs, sandy open areas, and along roadsides and railroads. It is cultivated statewide and commonly escapes into natural habitats.
Native perennial wildflower. A longtime favorite for native wildflower gardening; attracts butterflies and other pollinators, naturalizes readily. Commonly used in highway plantings.
Coreopsis is frequently planted along roadsides for beautification.
Several species in this genus are cultivated as garden ornamentals and for use as cut flowers. "Doubled" cultivars with numerous ray florets have been developed. In gardens, coreopsis demands excellent drainage and full sun but seems to prefer poor soil. It can self-seed abundantly and is good for naturalizing in wildflower gardens, rock gardens, meadows, and other places where a formal look isn't necessary. Deadheading the spent flowerheads can help prevent it from spreading, but it also reduces seed available for goldfinches and other birds.
Coreopsis (pronounced corry-opp-sis) is one of several plants whose common name is the same as the genus name. Others include iris, forsythia, gladiolus, zinnia, chrysanthemum, petunia, and asparagus. There are many more examples!
A memorable chuckle in James Thurber's classic 1939 short story "The Secret Life of Walter Mitty" comes when the vague protagonist daydreams that he is a famous surgeon performing a critical and risky operation. After Mitty heroically repairs the hospital's "anaesthetizer," using only a ballpoint pen, another surgeon checks the patient, turns pale, and whispers that "Coreopsis has set in." He nervously asks Mitty to take over, and the confident Mitty slips on his white gown and surgical gloves and prepares to save the patient.
The seedlike fruits of members of the sunflower family are called achenes. These provide food for birds and small mammals.
The foliage of various species of Coreopsis is browsed by a variety of herbivore mammals such as woodchucks, rabbits, and deer.
The flowers attract a wide range of pollinating insects including butterflies, skippers, bees, wasps, flies, beetles, moths, and more.
One longhorn bee species, the coreopsis longhorn bee (Melissodes coreopsis), is named for its fondness for visiting members of genus Coreopsis, but it has been recorded on several other kinds of flowers as well.
Many insects feed on coreopsis leaves, flowers, or other plant parts. Moth caterpillars that feed on coreopsis include at least three members of the geometrid or "looper" family: the dimorphic gray, the wavy-lined emerald, and the common tan wave. At least two species of calligraphy beetles (genus Calligrapha, in the leaf beetle family) feed on coreopsis: the ragweed leaf beetle (C. bidenticola) and the coreopsis leaf beetle (C. californica); both of these are attractive, boldly marked beetles.
In China and Japan, tickseed coreopsis was introduced as an ornamental and was planted to help prevent erosion and to beautify along railroads and other disturbed soils. But in those regions and in parts of Australia, where it is not native, it has proven to be invasive. In Japan, it is considered one of that nation's worst invasive species.