Royal Fern

Osmunda regalis var. Spectabilis

royal fern

Royal fern, photographed at Loxahatchee National Wild Life Refuge, Boynton Beach, Palm Beach County, in January 2020.

There are places on God's good earth where royal fern, in one form or another, doesn't grow. Just not many. Royal fern is everywhere, one of the few plants to be found on six of the seven continents. We qualify that statement slightly because of a taxonomic difference of opinion over whether royal fern is really one species or two that are closely related. More on that in a bit.

Royal fern, Osmunda regalis var. Spectabilis, is a Florida native found in all 67 counties of the Sunshine State. It's also found throughout eastern and central North America, as far north as Newfoundland and Saskatchewan and as far south as Florida and Louisiana. It likes wet places, dome swamps, shallow swamps and marshes, bogs, stream banks and the like.

In the language of botantists, royal fern is double pinnate in form, meaning its fronds are twice compound. The first two photos below show a single fern frond, the equivalent of a single leaf in other plants. Each "branch" coming from that central stem, or vein, is a pinna, or leaflet, aligned opposite each other, which are in turn made up by a number of pinnules that are slightly offset from each other, or in an alternate pattern. The effect is a rather unfernlike looking fern.

Royal fern, like all ferns, reproduces by spores rather than seeds. Spring is "blooming" season, for a lack of a better term, when spore producing parts form on the fronds. These fertile fronds don't fully unfurl the way the fronds shown on this page have, but instead arch inward and upward like plumes. Instead of bright green, they take on oranges, reds and browns, resembling flowers to some.

The name, royal fern, actually comes from Europe. Early naturalists believed our guy was the same fern species as found in Europe and in most of the rest of the globe. It got the name because it's one of the largest and most beautiful of ferns found on the continent.

Our version, the New World version of royal fern, and the European, or Old World version, are still considered the same species, just different varieties, or subspecies. The Old World royal fern is known as regalis (Osmunda regalis var. regalis), the American as spectabilis. Some argue that the two varieties are actually separate species.

There are various theories as to the origin of Osmunda. Some say it comes from the Saxon word for domestic peace, the Saxon word for god-protector, a name for the Viking god, Thor and a combination of Latin words for bone and to cleanse, referring to the plants' medicinal uses. There's also a legend that the wife and daughter of a waterman named Osmund hid themselves among the ferns during a Danish invasion of England. Take your pick.

Royal fern, whether it's one species or two, has been a mainstay of herbalists everywhere it's found. It's been used to treat chronic coughs, diarrhea, jaundice, worms, arthritic pain, cuts and bruises. The Iroquis made a tea from it to treat various conditions. It has had horticultural uses as well — the fibrous roots have been used commercially as potting material for epiphytes and orchids.

Globally, the royal fern population is secure, but it is endangered in parts of its range. Iowa considers it threatened; New York lists it as exploitably vulnerable and Florida classifies it as commercially exploited.

Royal fern is a member of Osumdaceae. Other common names: flowering fern, royal flowering fern and buckhorn break.

Click on photo for larger image

Published by Wild South Florida, PO Box 7241, Delray Beach, FL 33482.

Photographs by David Sedore. Photographs are property of the publishers and may not be used without permission.