Ferns - Osmunda Regalis

Family: Osmundaceae
Species: Osmunda regalis
Common name: Osmunda regale, Florida fern - Deutsch: Königsfarn-English: Royal fern

Etymology

The etymology of the generic name Osmunda is unclear: it may derive from the Icelandic “ass” or “oss” (god) and “munder” (gift). The specific name “regalis” alludes to the plant’s imposing size.

Description

A magnificent pteridophyte—one of the largest found in our regions—O. regalis has a large, blackish, highly branched and spongy rhizome, covered with the remains of previous fronds. In spring, the woolly and fragile stems unfurl first, revealing the sterile fronds, which are majestic, large, and erect, and are bipinnate with 7–9 pairs of ovate-lanceolate pinnules up to 9 cm long, green in colour. Then, in summer, the fertile fronds develop at the tops of the stems; they are longer but more slender, erect, rigid, and golden-brown in colour, resembling inflorescences and bearing the spores.

Habitat 

Widespread across Europe, Africa, Asia, and North America, it is the only European species in the Osmunda genus.

Properties and Uses I

n some countries, the young shoots are used in the preparation of traditional dishes.

Notes and Curiosities 

O. regalis belongs to a very ancient genus considered a relic from the Tertiary Era. Fossilised remains have been found, and the species survived the last glaciations thanks to the mild climate of coastal wetlands. In much of Europe, it is in decline due to the reduction of marshy areas. In certain regions of Italy where it was once abundant, it has even been threatened with extinction because blocks of soil containing its root system were indiscriminately removed by horticulturists seeking a particular soil type for orchid cultivation. In the wild, it is a protected species, usually growing in sunny peatland or marshy areas alongside willows or alders.

According to folklore, if on Midsummer’s Night (St John’s Eve) the “seed” of the fern glows like gold, it will reveal hidden earthly treasures, based on the belief that the special spore is akin to gold. Sometimes it was also believed that the “flower” of the fern would open on Christmas night, and whoever found and picked it would become rich (though this is quite impossible, as ferns do not produce flowers). Since these two collection times—St John’s Eve and Christmas—coincide with solstices, people may have regarded the fern’s supposed seed or flower as vegetal manifestations generated by the sun during these pivotal points in its cycle.

In the Andre Heller Botanical Garden, O. regalis is among the most significant species, offering a splash of soft green with a light, somewhat disorderly growth habit. In winter, the vegetation disappears, making spring the most fascinating season to admire it, as the still-coiled “fiddleheads” (or pastorals) emerge amid flowerbeds or near ponds, serving as a charming decorative element.

The understorey of the Gardone Riviera botanical park harbours numerous fern species, each with distinct traits and growth patterns. Some notable examples include:

• Dicksonia antarctica: A tree fern from Tasmania and New Zealand. It rarely thrives in our climates, yet it survives here in the park. Considered a living fossil dating back to the Jurassic, it features an expansive tuft of lightweight foliage where fertile and sterile fronds overlap at the top of a rhizome that rises like a trunk.

• Dryopteris filix-mas: Known as the male fern—historically mistaken for the male form of Athyrium filix-femina. It is also referred to as oak fern (or tree fern), referencing the woodlands where members of this genus flourish.

• Phillitis scolopendrum: Called the deer-tongue fern for its undivided, ribbon-like fronds. They are glossy and leathery, with elongated sori on the underside arranged slightly obliquely relative to the central vein of the leaf.

• Polystichum spp.: An evergreen fern with glossy green foliage, named for the sori set out in multiple rows.

• Thelypteris palustris: A marsh fern native to Eurasia and North America. It has a creeping stem about 2.5 mm in diameter, from which erect leaves up to 50 cm tall of bright green arise. In the Heller garden, it can be spotted in lower, waterlogged parts of ponds or in consistently damp patches of soil.

• Cyrtonium falcatum
  This is a "holly fern," so called because of the design of its leaf veins, which rejoin to form an arch. The specific epithet highlights the sickle‐like shape of the pinnules (the “leaves” of the ferns). The small sori are scattered irregularly on the frond's lower surface. Having become naturalized in our areas, it embellishes the rocky zones of the garden.

• Platycerium alcicorne
  This is an evergreen fern with lobed, erect, and arched fronds of grey-green color, covered by a dense pubescence resembling a moose's antlers. It is a subtropical and tropical epiphytic plant that grows in the crevices of other plants. In the Heller Garden, it can be admired above the colossal wisteria.

Ferns belong to the group of pteridophytes as they never produce flowers and cannot reproduce via seeds. In summer, many elongated or rounded outgrowths of reddish-brown color become visible on the underside of the fronds. These protuberances, called sori, are initially protected by a thin membrane known as the indusium and consist of clusters of small granules called sporangia. Each sporangium is a microscopic capsule containing a dark powder of reproductive cells called spores. When mature, the sporangium opens and disperses its contents into the wind. If a spore lands in a favorable spot, it gives rise to a tiny leaf called a “prothallus,” from which the fern will develop.