Flowering Fern

''Osmunda regalis'', or royal fern, is a species of deciduous fern, native to Europe, Africa and Asia, growing in woodland bogs and on the banks of streams. The species is sometimes known as flowering fern due to the appearance of its fertile fronds.

Description

Royal fern is a large perennial herb with stout ascending rhizomes that over many years build up a woody, trunk-like base covered by interwoven roots, 1 m or more high. The fronds, or leaves, arise directly from this rhizome and are very large, typically up to 120 cm but exceptionally as much as 400 cm long and 30-40 cm broad. Each frond is bipinnate, with 5–9 pairs of pinnae up to long, each pinna with 7–13 pairs of pinnules long and broad. Many of the fronds have a terminal fertile portion, where the blade is reduced almost to the midrib and densely covered with brown sporangia.

The fronds are at first covered with golden-brown hairs which quickly disappear, leaving a smooth, pale green surface to the leaves. Veins are prominent on both surfaces.

In the gametophyte stage, the prothallus is a small, green, fleshy plant just a few millimetres in size.

Distribution and status

The native range of royal fern is throughout Europe, North Africa and the Middle East as far as Iran, from Norway south to Algeria. It is listed as introduced in New Zealand, but its presence throughout North America is based on the taxonomic uncertainty about whether '' Osmunda spectabilis'' should be considered a separate species or not.

In many areas, ''O. regalis'' has become rare as a result of wetland drainage for agriculture.

Taxonomy

The name ''Osmunda'' possibly derives from ''Osmunder'', a Saxon name for the god Thor. The name "royal fern" derives from its being one of the largest and most imposing European ferns. The name has been qualified as "old world royal fern" in some American literature to distinguish it from the closely related American royal fern, '' O. spectabilis''. However this terminology is not found in British literature.

Evolution

The oldest known fossils of '' Osmunda'' date to the Paleocene, ''Osmunda'' likely derives from fossil species currently assigned to ''Claytosmunda''.

Varieties

There are three to four varieties as traditionally construed:
*''Osmunda regalis'' var. ''regalis''. Europe, Africa, southwest Asia. Sterile fronds to 160 cm tall.
*''Osmunda regalis'' var. ''panigrahiana'' R.D.Dixit. Southern Asia (India).
*''Osmunda regalis'' var. ''brasiliensis'' (Hook. & Grev.) Pic. Serm. Tropical regions of Central and South America; treated as a synonym of var. ''spectabilis'' by some authors.
*''Osmunda regalis'' var. ''spectabilis'' (Willdenow) A.Gray. Eastern North America. Sterile fronds to 100 cm tall. Now accepted as a separate species, ''Osmunda spectabilis''.

Similar species

There are three very similar species, '' Osmunda spectabilis'', '' Osmunda lancea'' and ''Osmunda japonica''. Recent genetic analysis (Metzgar et al., 2008) has shown that the New World varieties are in a clade that is sister to the Old World varieties of ''Osmunda regalis''. If this is true, then ''O. lancea'' and ''O. japonica'' should either be regarded as varieties of ''O. regalis'', or, conversely, ''O. regalis var. spectabilis'' should be regarded as a separate species, ''Osmunda spectabilis'' Willdenow. The var. ''brasiliensis'' would then be ''Osmunda spectabilis'' Willdenow var. ''brasiliensis'' Hooker & Greville.

Cultivation

''Osmunda regalis'' is widely cultivated in temperate regions. The species and the cultivar 'Cristata' have both gained the Royal Horticultural Society's Award of Garden Merit. Osmunda plants should be planted in preferably acidic, moist soil, associating well with other large moisture-loving plants such as ''Rodgersia'' and ''Gunnera''. However, it tolerates a range of soil and climatic conditions.

Other uses

The roots, along with those of other species of ''Osmunda'', are used for the production of osmunda fibre, used as a growing medium for cultivated orchids and other epiphytic plants.

According to Slavic mythology, the sporangia, called "Perun's flowers", have assorted magical powers, such as giving their holders the ability to defeat demons, fulfill wishes, unlock secrets, and understand the language of trees. However, collecting the sporangia is a difficult and frightening process. In earlier traditions, they must be collected on Kupala Night; later, after the arrival of Christianity, the date is changed to Easter eve. Either way, the person wanting to collect Perun's flowers must stand within a circle drawn around the plant and withstand the taunting or threats of demons.

The young shoots of the fern are, along with the similar shoots of many other fern species, known in some places as fiddleheads, and eaten as food, thought to have an asparagus-like taste.

References

*Hyde, H. A., Wade, A. E., & Harrison, S. G. (1978). ''Welsh Ferns''. National Museum of Wales.
*Metzgar, Jordan S., Judith E. Skog, Elizabeth A. Zimmer, and Kathleen M. Pryer (2008). "The Paraphyly of Osmunda is Confirmed by Phylogenetic Analyses of Seven Plastid Loci." Systematic Botany, 33(1): pp. 31–36

External links

Flora Europaea: ''Osmunda regalis''Flora of North America: ''Osmunda regalis'' var. ''spectabilis''Florida Institute for Systematic Botany: ''Osmunda regalis'' var. ''spectabilis''
(including var. ''brasiliensis'' as a synonym)

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Osmundales
Plants described in 1753
Taxa named by Carl Linnaeus
Ferns of Africa
Ferns of Asia
Ferns of Europe
Garden plants of North America