Fern Fiddleheads: The Succulent Stalks of Spring
Almost everyone has heard of "fiddlehead ferns," a gourmet wild vegetable found across much of North America in the springtime. Few wild edibles are so well known, so convenient and tasty, or so widely available. Yet unfortunately, few of them are surrounded by so much confusion. Many people mistakenly believe that all fern fiddleheads are edible. Not surprisingly, stories of people getting sick from fiddleheads are common, and this has caused many to steer clear of these wildlings. All of this confusion is unnecessary, for learning to identify the edible species of fiddleheads is rather easy - and the reward is a lifetime of free and delicious vegetables.
There are three main species of edible ferns in North America: ostrich fern Matteucia struthiopteris, lady fern Athyrium filix-femina, and bracken fern Pteridium aquilinum. All of them are widespread and, in certain areas, abundant. For each of these species the part gathered and eaten is the young, tender shoot (called fiddleheads due to the curled tips, which resemble the top of a fiddle) found in spring and early summer. The mature fronds of all of these ferns should not be eaten.
When people say "fiddlehead fern" they are most often talking about the ostrich fern. This is the species often available in produce markets and sometimes even on the menus of fine restaurants. These magnificent ferns grow mostly in shady river bottoms, where often they cover many acres of ground, but they are also occasionally found in rich hardwood forests. Ostrich fern ranges from Newfoundland to Alaska and British Colombia, south to northern California, the Midwest, and the Southern Appalachians. It is abundant in the upper Great Lakes, the Northeast, and much of southern Canada.
Ostrich ferns grow from three to six feet tall. The five to nine fronds (leaves) of each plant are arranged in a rosette forming a large funnel. The fronds emanate from a large rootstock or rhizome, which looks like a scaly clump or mound. Ostrich ferns bear their spores on separate, brown fronds which are smaller than the others and stand erect in the middle of the cluster. These are often collected for dried flower arrangements.
Of course, you’re looking for fiddleheads, not full-grown fronds. The fiddlehead stalks are smooth and naked of any scales or wool, but the coiled tops are full of brown papery flakes. The top side of the stalk (or, the part facing the center of the rosette) has a deep, U-shaped trough running its entire length - this is an important feature to look for.
Gather the fiddleheads in mid to late spring; they’ll be too old by the time the leaves are fully formed on the sugar maples and oaks. Harvest them when they are eight to twenty inches tall - as long as they are still tender and the leafy portion of the frond is not yet unfurled. Usually the bottom quarter or so of the stalk is too tough to eat; in time you’ll get the hang of knowing where to break them off. You don’t have to cut the fiddleheads; when bent they should snap off cleanly.
Many people only collect the tightly coiled tops of the fiddleheads, leaving behind the juicy stalk which constitutes the greater part of the shoot. I have never been able to figure out why this is done - there is no gustatory, culinary, or practical reason for it. In fact, I greatly prefer both the flavor and the texture of the stalks to that of the coiled leafy tips. Your fiddlehead patch will yield a lot more good food.
Ostrich fern is easy to gather in great quantities and for that reason has long been stored away for the winter by canning, a tradition that I still carry on. I just open a jar at my convenience and use it in a soup or casserole. But canned fiddleheads are not half as good as the fresh vegetables. Simply boiled or steamed and served with butter like asparagus they are superb. Ostrich fern shoots are crisp and sweet when raw and make a pleasant addition to salads or can be just nibbled on a hike through the woods. However, they should not be eaten in large quantities raw.
A Note on Cinnamon and Interrupted Ferns
Cinnamon fern Osmundea cinnamomea is common on sandy soil in partial shade where the water table is close to the surface. Interrupted fern Osmundea claytonia is abundant in wooded areas across much of the range of ostrich fern and likes partial shade on rich, moist to mucky soil. In the fiddlehead stage, these two large rosette ferns are often confused with ostrich fern. Both can be easily discriminated by the presence of wool covering the fiddleheads and by the absence of the U-shaped groove running the length of the stalk.
Many people believe that one or both of these ferns are the "true" edible fiddlehead ferns. Thousands of people collect and eat these ferns every year despite the fact that they are mildly toxic. I have, on numerous occasions, seen published photographs of interrupted ferns mislabeled as one of the edible species. Undoubtedly this misunderstanding is what accounts for most of the sickness associated with eating fiddleheads.
The problem is that these ferns are only mildly toxic, and their bitter taste (which I find detestable) is apparently not repulsive to everyone . Thus it is entirely possible to nibble only one or two raw, or to throw a handful of the chopped-up stalks into split-pea soup, and not feel sick. However, the consumption of a large serving of cooked cinnamon or interrupted fern fiddleheads, or just a moderate serving when raw, can result in nausea, dizziness, lethargy, and headache. I advise against eating them, although many people do.
The lady fern is found scattered in moist conifer and deciduous forests, where it tolerates a high degree of shade. This fern, commonly used in landscaping, ranges from coast to coast and is abundant in the northern U.S. and much of Canada. Its rosettes usually consist of three to seven fronds which rise from two to three and a half feet above the forest floor. This species also exhibits a groove running down the top of its stalk, only it is proportionately smaller than that of the ostrich fern. The spores of lady fern are borne on the underside of the frond rather than on a separate one like ostrich fern.
Bracken fern is the common, large fern with a single, erect stem, of northern and mountainous regions. By biomass, it is probably the most prolific herbaceous plant in North America and in the world.
There is a great deal of debate about the edibility of bracken fern. On one hand, there is an enormous body of ethnographic evidence that it is edible. It is regularly eaten by hundreds of millions of people today, and in North America was a traditional food for many Native American cultures. Compare this to ostrich fern, which is consumed by far fewer people today and for which there is virtually no evidence that Native Americans traditionally consumed it anywhere. Despite this, a search on the internet will turn up hundreds of sources telling you that this plant is poisonous, even deadly, and should never be eaten. This is due to the presence of a very potent carcinogen called ptaquiloside. However, ptaquiloside is not heat-stable and is apparently destroyed by cooking. Interestingly, Americans don't seem too worried about the equally well-established facts that bread crust and grilled meats contain potent carcinogens. And orientals don't seem to worried about bracken fern.
While it is advisable to eat all fiddleheads cooked, bracken fern fiddleheads should definitely be cooked to destroy the ptaquiloside.