Door County Ferns to Preserve

These small delicate Maidenhair Spleenwort Ferns often hug the mossy vertical rock ledges. Photo by Roy Lukes.

If teachers had told me as a small boy that the coal my dad burned in the basement furnace to heat our home was originally formed in part from the carbonized remains of ferns resembling those dad grew along the shaded north side of our home, I would have had a hard time believing them.

Dad was especially fond of the Maidenhair Ferns he transplanted from his woods on the farm to his raised Tuberous Begonia and fern bed north of the house. Undoubtedly that’s where I developed my attraction to ferns about 1937.

Ferns made their appearance on Earth during the Carboniferous Period, also known as the Age of Ferns, which began about 260 million years ago and lasted for nearly 25 million years.

Fern fossils are commonly found in coal-producing states where the original plant tissue has been preserved as a thin carbonaceous film between layers of sedimentary or metamorphic rocks.

Tree-size ferns, some with stems 3½ feet in diameter, grew along with gigantic club mosses in dense swampy forests. They died, and today their carbonized remains help make the coal fields of the world. One modern-day fern in Tahiti grows to about 60 feet in height.

Even though the family of ferns is very large, numbering about 10,000, the great majority of them are restricted to tropical regions. In fact, it is a rather easy group of plants to master with only approximately 30 species growing in northeastern Wisconsin. They range from the extremely abundant (weedy) Bracken to the rare Christmas, Maidenhair Spleenwort, Green Spleenwort and Moonwort Ferns.

Extremely abundant and widespread Bracken Ferns clothe the mountain slopes of Scotland as well as hundreds of miles of roadsides throughout Wisconsin, especially where it is not too shady.

It is during the latter part of summer, when many insect species are on the wane, that we prefer to enjoy the refreshing coolness of a well-preserved woods rich with ferns. A feature of most ferns that we admire is the rather demanding set of growing conditions for each particular species.

The Maidenhair Fern is quite common throughout Door County. Photo by Roy Lukes.

Some of these species are so rare that we are reluctant to share their location with others. True or not, I believe in an old saying: “Tell one person and you’ve told six. Tell two people and you’ve told 66.” Eventually the “wrong” people learn of the rare plant locations and the plants disappear.

It would be exciting to visit our national capitol in Washington, D.C. some day and, among other historical and inspiring sites, tour the National Arboretum. One of the highlights we’ve been told about is Fern Valley, existing in what used to be a 3½-acre ravine filled with mostly trash, honeysuckles and poison ivy.

Several women accepted a challenge and, through careful planning and very hard work, transformed an eyesore into a national treasure. Utmost of importance in this worthy project were strong leadership, simple but realistic objectives and a core of devoted, unselfish people. Tons of TLC was needed along with an annual “WW” corps, Women Weeders.

A map of the National Arboretum we were given indicates a self-guiding nature walk, the kind I like best, which introduces people to many wildflowers growing in with several dozen species of ferns. Much joy and learning can obviously be had right up to the time of freeze in this little fern paradise.

It was in the mid-60s that I learned from Emil Kruschke, curator of botany at the Milwaukee Public Museum at the time, that Christmas Ferns were considered to be non-existent in Wisconsin.

Then came that fall day of our unproductive mushroom hunt in western Kewaunee County in 1967 when unexpectedly a few unusual ferns appeared. Suddenly it became apparent that we were staring at genuine, living, healthy Christmas Ferns. We realized the more we looked that there were dozens of them, perhaps 150 or more, thriving in this rocky, hilly and shaded deciduous “treasure land!”

My discovery of that fern-rich wooded site in Kewaunee County changed that, and even the later discovery by friends of a few plants in Door County has added to their slim numbers. I’m firmly convinced that if enough interested people would get to recognize this plant, others would quickly be found in our county.

Deep green Christmas Ferns, growing in bouquet-like clusters, cascade from a central rootstock. They prefer rich limy soil in hardwoods, do well along wooded stream-banks, and appear to prefer heavily shaded rocky slopes. All their requirements appear to be fairly common in our county, even though these plants are rarely discovered here.

This tiny Green Spleenwort is extremely rare in Wisconsin. Photo by Roy Lukes.

As you might expect, many colonies have been practically exterminated due to excessive picking by florists and other people all intent on adding indoor greenery to the Christmas scene. It is ironic to think that this plant is being decimated in certain localities in order to symbolize, like other Christmas “greens,” the life everlasting. Other native plants of this region are also suffering the same fate, plants such as the Princess or Ground Pine and the Running Clubmoss.

Ferns are so fascinating and abundant throughout our state and are the perfect plants to enjoy in later August. It would be quite fantastic if every town in the entire state could have its own Fern Valley. I wonder how something as wonderful as this might be accomplished, possibly by a group such as the Master Gardeners.

Add a new dimension to your life by becoming more acquainted with the ferns. Your attitude toward our natural world will be greatly improved as will your sense of wonder. Ferns are truly spectacular plants.

To discover nature at her finest, to search for, find and feel beauty is to many one of the greatest and most rewarding privileges in life. To ensure that future generations may enjoy the same things should be a high priority for every citizen of this great country. Good luck with your Fern Valley!