This is part 1 of all those ferns and fern- allies growing on the British Isles as well as many other countries in the temperate or even tropical world!

Ferns flourished before all the flowering plants came on earth and still thrive in many niche areas all over the world.
It is a large and divers group and a short account of their classification follows on the next page. For each group there may be one or two important species which have some story to tell or ethnobotanical use!
Below is a lovely short poem about the Ferns, written for the former students of and by Ian Trueman, Emeritus Professor in Plant Ecology, University of Wolverhampton several years ago.
Ferns
When the green weeds rose from the sea
We, the great-leaved plants, were the last to raise our heads.
But we soon became perfect in the horsetail forests,
When the coal was being made in sun and steam.
And there, quiet under the bristle-leaved trees
We became perfect, as you see us now.
And quiet, and secret, and everlasting
We still unfold our ancient dance
Under the proud stems of our seed-borne sons.
Links are provided from various websites for you to look into each group or plant a bit further. Such as the Online Atlas of the British and Irish Flora, where you can find out exactly where it grows in the B.I. This time I used copies of prints of ‘The Ferns of Great Britain and Ireland’ as well as pictures sourced through Wikipedia Common. Medicinal uses from ‘The Medicinal Flora of Britain and Northwestern Europe’ by Julian Barker. But please note this is an educational blog only and going out harvesting rare plants is not advisable for use as medicine and should be left to a qualified herbalist! Pictures by Matt Summers unless stated. FBBC is added behind name in the Contents page if the plant in question is mentioned or/and described in the Flora of Birmingham and the Black Country.
You can listen to this radio play by Brett Westwood called Natural Histories: Ferns: https://www.bbc.co.uk/sounds/play/m000b80h
General information and classification of Ferns:
The PTERIDOPHYTES or Ferns & Fern-allies have varied habit and leaf structure but are distinctive from the flowering plants in that they do not bare flowers but have spores and spore structures, which are an important identification feature.
The life cycle of the fern has two different stages;
- sporophyte, which releases spores, and
- gametophyte, which releases gametes.
Gametophyte plants are haploid, sporophyte plants diploid. This type of life cycle is called alternation of generations. To follow the life cycle of the fern, begin at number one in the diagram of this link.
Stace divides all the ferns and fern-allies into 4 informal large groups:
- Lycophytes with 1) Lycopodiaceae – Clubmoss family 2) Selaginellaceae -Lesser clubmoss family and 3) Isoetaceae – Quillwort family
- Eusporangiate ferns with 4) Ophioglossaceae- Adder’s tongue family
- Calamophytes with 5) Equisetaceae – Horsetail family AND
- Leptosporangiate ferns or True ferns with 16 families (see with entry there)
Please use the jump-links provided in the Contents to quickly get to the family you want on the next page.
Contents:
The LYCOPHYTES
1 LYCOPODIACEAE – Clubmoss family
Huperzia selago or Fir Clubmoss FBBC
- Lycopodium clavatum or Stag’s-horn Clubmoss
- L. annotinum or Interrupted Clubmoss
- L. lagopus or Hare’s-foot Clubmoss
2 SELAGINELLACEAE – Lesser clubmoss family
- Selaginella selaginoides or Lesser Clubmoss
- S. kraussiana or Krauss’s Clubmoss (neophyte) FBBC
3 ISOETACEAE – Quillwort family
- Isoetes lacustris or (Lake) Quillwort
- I. echinospora or Spring Quillwort
- I. histrix or Land Quillwort
The EUSPORANGIATE FERNS
4 OPHIOGLOSSACEAE – Adder’s-tongue family
- Ophioglossum vulgatum or Adder’s-tongue FBBC
- O. azoricum or Small Adder’s-tongue
- O. lusitanicum or Least Adder’s-tongue
- Botrychium lunaria or Moonwort FBBC
- B. nordicum or Nordic Moonwort
CALAMOPHYTES or Horsetails
See also here:
https://wonderfulweedweekly.co.uk/the-horsetails/
5 EQUISETACEAE – Horsetail family
- Equisetum arvense or Field Horsetail FBBC
- E. fluviatile or Water Horsetail FBBC
- E. × litorale (Equisetum arvense × fluviatile) or Shore Horsetail FBBC
- E. hyemale or Rough Horsetail FBBC
- E. palustre or Marsh Horsetail FBBC
- E. pratense or Shady Horsetail
- E. ramosissimum or Branched Horsetail
- E. sylvaticum or Wood Horsetail FBBC
- E. telmateia or Great Horsetail FBBC
- E. variegatum or Variegated Horsetail
- E. × trachyodon (Equisetum hyemale × variegatum) or Mackay’s Horsetail
The TRUE FERNS or LEPTOSPORANGIATE FERNS
6 OSMUNDACEAE or Royal Fern family
Osmunda regalis or Royal Fern FBBC
7 HYMENOPHYLLACEAE – Filmy-fern family
- Hymenophyllum tunbrigense or Tunbridge Filmy-fern
- H. wilsonii or Wilson’s Filmy-fern
- Trichomanes speciosum or Killarney Fern
8 MARSILEACEAE – Pillwort family
Pilularia globulifera or Pillwort FBBC
9 SALVINIACEAE – Water fern family
Azolla filiculoides or Water Fern FBBC
9A CYATHEACEAE
LYCOPHYTES
The LYCOPHYTES
1 LYCOPODIACEAE – Clubmoss family
Huperzia selago or Fir Clubmoss FBBC
A decumbent, evergreen, perennial, gemmiferous clubmoss found on acidic, nutrient-poor, sandy or peaty soils in upland and montane grasslands and heathlands, blanket bog, montane scree and ledge communities and, rarely, sand quarry tips. Spread is primarily through vegetative means.

Lycopodium clavatum or Stag’s-horn Clubmoss FBBC
This is the best known of 3 native species. The other 2 are:
A prostrate, evergreen perennial herb of heaths, moors and mountains.
The spores of this moss, “lycopodium powder“, are explosive if present in the air in high enough densities. They were used as flash powder in early photography and magic acts.
Traditional Medicinal Use:
The oily yellow mature spores can be used fro inflamed skin especially babies and the elderly. The infusion of the entire plant can be used for inflammations of the bladder!
tablets for symptoms of excessive flatulence, anxiety and headaches. Also see this website on medicinal uses.
2 SELAGINELLACEAE – Lesser clubmoss family

Selaginella selaginoides or Lesser Clubmoss
In Britain and Ireland it had mostly disappeared from lowland areas by 1930, but its distribution in upland areas remains largely unchanged.
S. kraussiana or Krauss’s Clubmoss (neophyte) FBBC
3 ISOETACEAE – Quillwort family
This has 3 native species, the best known one is:

Isoetes lacustris or (Lake) Quillwort
A submerged aquatic perennial found in oligotrophic lakes with a rocky or skeletal substrate. It frequently forms extensive lawns of many square metres at depths up to 2.5 m and rarely deeper (6 m in Loch Lundie, Westerness). It occasionally colonizes artificial reservoirs. It often grows with I. echinospora, and not infrequently hybridizes with it.
The lake quillwort has many long, narrow leaves from 8–20 cm long and 0.5–2 mm broad, widening to 5 mm broad at the base. There is a sac that produces the spores at the bottom of each leaf base. The plant has a very short stem, called a corm, where all the leaves and roots are attached close together. It does not have traditional roots, but instead some of its leaves are modified to act like roots. These pseudo-roots are called rhizomorphs, and are attached to the bottom end of corm. The upper leaves are green and found sprouting in a clump.
Reproduction usually takes place during the late summer or early autumn. The sacs at the bottom of leaves create two types of spores, female (megaspores, about 0.5 mm diameter) and male (microspores, a few micrometres in diameter). These spores represent the gametophyte phase of the life cycle.
Uses:
This species is one of a few cultivated species of quillworts, either as an aquarium plant or as an educational resource.
thew 2 other species are:
EUSPORANGIATE FERNS & OPHIOGLOSSACEAE
Then the EUSPORANGIATE FERNS
4 OPHIOGLOSSACEAE – Adder’s-tongue family
Has 3 native species, the best known is:

Ophioglossum vulgatum or Adder’s-tongue FBBC
Ophioglossum vulgatum grows from a rhizome base to 10–20 cm tall (rarely to 30 cm). It consists of a two-part frond, separated into a rounded diamond-shaped sheath and narrow spore-bearing spike. The spike has around 10-40 segments on each side.
Former Use:
Traditional European folk use of leaves and rhizomes as a poultice for wounds. This remedy was sometimes called the “Green Oil of Charity”. A tea made from the leaves was used as a traditional European folk remedy for internal bleeding and vomiting.
The other 2 species are:
- Botrychium lunaria or Moonwort FBBC
A small perennial fern, often occurring singly or in small populations, which may show marked annual fluctuations. It prefers well-drained sites, usually with a high base-content, although it can occur on more acidic substrates. Habitats historically included unimproved meadows, pastures, and even open woodland, but now it is most frequent by upland tracksides and on grassy rock ledges. In the lowlands it is a plant of fixed sand dunes, lead-mine waste, slag heaps, quarry spoil and low grass-heath associated with roadsides and disused runways.
Next the
CALAMOPHYTES or Horsetails
5 EQUISETACEAE – Horsetail family
There are 11 native species and numerous more hybrids mentioned in Stace of this fascinating and useful plant. The 9 species + 2 hybrids in Plant Atlas Online are listed below.
Equisetaceae is the only surviving family of the Equisetales, a group with many fossils of large tree-like plants that possessed ribbed stems similar to modern horsetails. Pseudobornia is the oldest known relative of Equisetum; it grew in the late Devonian, about 375 million years ago and is assigned to its own order.
Against Chronic degenerative processes; atherosclerosis; also in healing and repair of eg brittle nails and bones.
This interesting plant was covered in a former post, see link.

- Equisetum arvense or Field Horsetail FBBC
- E. fluviatile or Water Horsetail FBBC
- E. × litorale (Equisetum arvense × fluviatile) or Shore Horsetail FBBC
- E. hyemale or Rough Horsetail FBBC
- E. palustre or Marsh Horsetail FBBC
- E. pratense or Shady Horsetail
- E. ramosissimum or Branched Horsetail
- E. sylvaticum or Wood Horsetail FBBC
- E. telmateia or Great Horsetail FBBC
- E. variegatum or Variegated Horsetail
- E. × trachyodon (Equisetum hyemale × variegatum) or Mackay’s Horsetail
Finally the TRUE FERNS or LEPTOSPORANGIATE FERNS
This has 16 families described in Stace. In this post we cover the first 4:
- 6) Osmundaceae – Royal Fern family
- 7) Hymenophyllaceae – Filmy-fern family
- 8) Marsiliaceae – Pillwort family
- 9) Salviniaceae – Water fern family
- 9a) Cyatheaceae ( for the non-native Cyathea dealbata)
6 OSMUNDACEAE or Royal Fern family


Osmunda regalis or Royal Fern FBBC
A large fern of neutral or acidic substrates in wet heathland, blanket bog, fen-carr woodland and ditches, and occasionally on riverbanks, rocky lake shores, limestone sea cliffs, mires and sand dune-slacks. In western Ireland it also grows in wet fields. It is often confined to inaccessible sites in grazed areas.
The species is sometimes known as flowering fern due to the appearance of its fertile fronds. It produces separate fertile and sterile fronds.
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.
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.
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.
Seasoned royal fern is also used in the dish Namul in Korean royal court cuisine.
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.
For bruising, bleeding and sores (both internal and external); deep litter mattresses of fresh fronds were prepared to relieve rheumatic pain and stiffness, and also for children with rickets!
7 HYMENOPHYLLACEAE – Filmy-fern family
These are beautiful and often appear as very dark green or even black clumps and may be mistaken for a robust moss or liverwort. In most species, the frond, apart from the vascular tissue, is only a single cell thick, and they do not have any stomata. Therefore, they are very vulnerable to desiccation which limits the habitats in which they can survive!
A good collection used to be at the Royal Botanic Gardens, Kew in a special Filmy Fern House, next to the orangery.
This family has 2 native genera and 3 species:
Hymenophyllum tunbrigense or Tunbridge Filmy-fern
A rhizomatous, perennial, mat-forming fern of very sheltered, often deeply shaded, humid habitats; these include acidic rock faces, humic banks and tree trunks, particularly in deep wooded stream valleys, and crevices on upland boulder scree.
H. wilsonii or Wilson’s Filmy-fern
A rhizomatous perennial fern, forming dense colonies on a variety of substrates, including sheltered acidic or, rarely, mildly basic rocks, and trees in humid sites. It also occurs on damp upland cliffs, boulder scree and, rarely, old walls in hyper-humid areas.
Trichomanes speciosum or Killarney Fern. (gametophyte)
T. speciosum or Killarney Fern (sporophyte) = more rare!
A rhizomatous evergreen fern, with delicate but long-lived fronds, restricted to humid, winter-warm sites. The sporophyte occurs only in constantly damp, shaded localities, usually on acidic, but often base-flushed rocks, rarely on damp humic banks, and exceptionally as an epiphyte.



8 MARSILEACEAE – Pillwort family

Pilularia globulifera or Pillwort FBBC
A small, rhizomatous fern growing on the edges of non-calcareous lakes, reservoirs, ponds or slow-flowing rivers, and sometimes on damp mine workings or as a submerged aquatic.
Pillwort can be grown in a “bog garden” or as a marginal aquatic in a garden pond.
9 SALVINIACEAE – Water fern family


Azolla filiculoides or Water Fern FBBC
A floating neophyte fern of canals, ditches, ponds and sheltered bays in lakes and rivers. It is most frequent in calcareous water, or near the sea.
It gives complete coverage of the water in only a few months. Each individual plant is 1–2 cm across, green tinged pink, orange or red at the edges, branching freely, and breaking into smaller sections as it grows. It is not tolerant of cold temperatures and, in temperate regions it largely dies back in winter, surviving by means of submerged buds. It harbors the diazotrophic organism, Nostoc azollae, in specialized leaf pockets. This ancient symbiosis allows N. azollae to fix nitrogen from the air and contribute to the fern’s metabolism.
The species has been introduced to many regions of the Old World, grown for its nitrogen-fixing ability that may be used to enhance the growth rate of crops grown in water, such as rice, or by removal from lakes for use as green manure.
Banned From Sale after April 2014. An invasive, non-native plant.
Water fern is a small free-floating water plant that forms dense mats. It was introduced for ornamental use in ponds and aquaria but its introduction into the wild has meant it has spread rapidly throughout England in the last 50 years.
What’s the problem?
It spreads mainly vegetatively, which makes it difficult to eradicate as it only takes a small section to float downstream to start a new colony, but it can also spread by producing minute spores. It out-competes native species by forming a dense covering on the surface of the water. This blocks out light and can also deoxygenate the water. The dense mats can also appear to be a solid surface so animals and humans can fall into the water.This species is listed on Schedule 9 of the Wildlife and Countryside Act in England and Wales therefore, it is also an offence to plant or otherwise cause to grow these species in the wild and after April 2014 this species will no longer legally be for sale in England and Wales.
9A CYATHEACEAE
This is an ornamental tree fern family with the dubious record of the Silver tree-fern or Cyathea dealbata which is endemic to New Zealand.
