Into The Wild

Finding Ferns

While out exploring this summer, look beyond the wildflowers to discover a sublime survivor from the age of the dinosaurs.

Compiled by Stephanie Folk

Bracken Fern

Bracken fern is common, particularly in oak woods with sandy soil. Resembles greenery used in floral arrangements. Though its fronds grow no longer than three feet, the bracken fern’s root system can stretch underground for acres, making it one of the largest plants on Earth.

 

Walking Fern

Quite literally walks its way along rocky surfaces, attaching to cracks in the rock. When the tip of the leaf touches the ground, it forms roots and grows another stem. Its solid, slender blades are not as feathery as a typical fern. Walking fern is quite rare here, so walk lightly if you come across it.

Cinnamon Fern, Interrupted Fern, and Royal Fern

These members of the Osmunda genus are found in the northern flatwoods, bogs, and sandy prairies. Cinnamon fern (shown here) can be identified by its cinnamon-colored spore-producing fronds, which are encircled by green infertile fronds. Interrupted fern has fronds that narrow abruptly in the middle, then widen again before tapering off at the tip. Royal fern is, appropriately, majestic. Light green and up to six feet tall, it creates the appearance of a lush fern jungle.

 

Lady Fern

Lady fern is fairly common in both high-quality and degraded woodlands. Its lush feathery fronds stand up to three feet high. You can look for this attractive fern at Ryerson Woods Conservation Area in Lake County.

Marsh Shield Fern

Marsh shield fern grows in sunny, wet areas, such as marshes, sedge meadows, and fens. Historically it was extremely common and probably covered thousands of acres. It’s not very common today, but you can spot it at the Nippersink Creek North Branch Conservation Area in McHenry County or at Volo Bog in Lake County.

Maidenhair Fern

Less common locally, maidenhair fern grows mainly in high-quality woodlands, often on sloping hillsides in sugar maple forests. This small fern (under 20 inches tall) has a delicate spray of leaves and a distinct shiny black stem that resembles a wire or a strand of hair.

Christmas Fern

The sandy, densely wooded sections of Indiana Dunes National Lakeshore are perfect places to find this light green fern, which can grow up to two feet. It gets its name because it’s evergreen, and easy to spot even in winter.

Sensitive Fern

Another species that is at home in sunny, damp habitats. While this species is very sensitive to frost, it can tolerate a range of conditions, growing in shade as well as sun. Look for smooth, light green fronds cut into long lobes with slightly scalloped edges.

Purple Cliff Brake

Grows in rocky areas, typically along limestone cliffs and outcroppings. This delicate fern is just 4 to 12 inches high, with a thin, wiry stem. Look for it along the rocky areas at Waterfall Glen in DuPage County.

Living Fossils

Plants from 300 million years ago are lurking in the natural areas of the Chicago region. Ferns are “a connection to the past,” says Ken Klick, restoration ecologist with the Lake County Forest Preserves. “They are one of the first forms of vascular plants, a few steps above mosses. They really were here when the dinosaurs were around. They’re that ancient.”

Complicated Love Lives

Ferns differ from flowering plants in their method of reproduction. Having no flowers or seeds, they instead cycle through two separate forms.

As a sporophyte — the form that most people would recognize, with distinct feather-like leaves, or fronds — they produce spores, which are dispersed by the wind.

Spores lucky enough to land in a suitable location grow into gametophytes, small amorphous or heart-shaped blobs that easily go unnoticed. The gametophytes produce eggs and mobile sperm. The sperm fertilize an egg, which then grows into an adult sporophyte. 

Fern sperm travel best through water, which is why most species are found in damp, shady habitats; however, some species have adapted to sun, dry conditions, and even life on rocky cliff faces.