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Yellow Coneflowers

© Gregg Pasterick

Speaking of yellow coneflowers...huh?

A few weeks back I wrote about the "real" Black-eyed Susan (Rudbeckia hirta), neglecting to ponder the rest of the yellow coneflowers in much detail. Well, this is their turn.

Yellow Coneflowers are happy, bright splashes of sunshine in prairies, open spaces, light woodlands, and along roadsides, just where you'd expect late-summer bloomers to be. Oh, and they are popular with gardeners (some of whom, I suspect, have no idea they adding a native wildflower to the flower bed, but we'll leave that our secret).

Members of that ol' familiar Composite or Aster Family (Asteraceae), they come in 2 genera (mostly), Ratibida and Rudbeckia. There are perhaps a half dozen species in the Ratibida genus, and as many as 20 species of Rudbeckia. Dracopis amplexcaulis, known simply as Coneflower, can be found from Georgia to Texas, north to Missouri and Kansas.

The Ratibida species are native to Mexico as well as North America, and are typically found in prairies. They have erect stems that branch in the middle, and bear solitary terminal flowers. Each flower head has long drooping yellow to yellow-brown ray flowers around a prominent cone-shaped center of disk flowers. They are all either biennials or perennials.

Gray-headed Coneflower (Ratibida pinnata), which is also called Prairie Coneflower in Ohio, is common in mesic to dry prairies, and was abundant in the prairie remnants of southern Ohio I visited each August. The central cone of disk flowers is less than 1" tall - usually taller than wide - and is gray, turning brown with age. Up to 13 petals (ray flowers) dangle from around the base of the cone. They bloom from July into October, and the seed-heads smell of anise when crushed.

Another member of the genus, the other Prairie Coneflower (R. columnifera), has a much taller central cone, more than twice as tall as it is wide. It grows in southwestern Canada down into the western and central U.S. R. columnifera f. pulcherrima, with its reddish-brown petals, is known as Mexican Hat, and is another popular wildflower that ends up in gardens.

Among the Rudbeckias we have Sweet Black-eyed Susan (R. subtomentosa), Thin-leaved Coneflower (R. triloba) and Green-headed Coneflower (R. laciniata). Thin-leaved Coneflower and Green-headed Coneflower were both very common at some locations in Ohio.

Thin-leaved Coneflower, also known as Brown-eyed Susan, and Sweet Black-eyed Susan Coneflower are 2 species that contribute to the Black-eyed Susan confusion. Both grow taller than Black-eyed Susan.