By George Ellison, lllustration by Elizabeth Ellison
“Here and elsewhere, bracken is such an aggressive plant that one wonders why it has not taken over the world.”
~ R. C. Moran, A Natural History of Ferns
I am a fern aficionado, not a fern authority. Nevertheless, ferns are my favorite plants. And bracken is one of my favorite ferns to observe—when it’s not on my property. I do have some company in this regard.
Bracken (Pteridium aquilinum) is said to be one of the five most common plants in the world. Standing up to five feet high (but usually about two and a half feet), it is the coarse, leathery fern you have almost certainly encountered in disturbed areas, thickets, and dry, open woodlands.
Along with devil’s walking stick (Aralia spinosa), bracken is one of the more intricately “designed” plants in our flora. The fronds are a maze of interrelated stems and segments that are a delight to behold. Its morphology is fairly complex and has, through the years, stimulated the descriptive resources of more than a few taxonomists. Other common names are eagle fern (because the fiddleheads as they are unfurling resemble the claws of an eagle) and hog fern (because feral swine fed on the plant).
Not many observers have anything positive to say about bracken. But I do. Ferns as a plant type have for millions of years explored the possibilities of leaf form and function. Ever attentive, Thoreau, as usual, summed it up: “Nature made ferns for pure leaves to show what she could do in that line.”
Indigo Buntings and Chestnut-sided Warblers like bracken, too. They nest in the disturbed areas that the fern favors and have discovered that the tri-pronged “cup” formed by the lower-most pinnae serves as the perfect support for nesting materials. Both species, in return, no doubt feed on the insects that feed on the bracken, which are many. Bracken attracts more than a hundred species including grasshoppers, bees, wasps, beetles, aphids, leafhoppers, bracken borers, and fern moth caterpillars.
However, bracken does have its negative aspects. It can be so invasive as to form an almost impenetrable ground cover that shades out less aggressive plant species. Dense stands can persist from rhizomes for hundreds of years.
Bracken also contains an array of poisons (including hydrogen cyanide) that cause vitamin deficiencies in livestock, “blind staggers” in horses, and death in humans. These poisons evolved as defenses against grazing animals and insects that chew, suck, and gnaw on the fronds.
Studies have verified that the incidence of stomach cancer increases in countries like England and Japan, where quantities of bracken fiddleheads emerging in spring are harvested. In Japan they are soaked overnight in cold water and then boiled and sautéed with onions, soy sauce, and sesame seed oil.