English translation by Ossi Kakko
NOTE! Botanical descriptions presented here are not full and may not be suitable for exact identification. Please consult your local botanists for proper identification.
Golden locks, sweet fern
Root of this fern has a sweet taste similar to a liquorice root, but it has also somewhat “burning” flavour. The root contains many different types of sugars, which are partially the same as that which is in real liquorice root.
This root has been dried and ground for its addition in baking flour, porridges and pancakes. It is also utilisable for herbal tea mixes, to bring some sweetness. For tea usage it is essential not to boil them in water so as to the prevent the more astringent sugars dissolving into the tea.
The traditional Norwegian drink called “siril” is prepared from the boiled hops and root of this fern.
A piece of the root can also be sucked in the mouth like a sweet candy.
In old times this fern has had also medicinal value. The root was harvested in early spring or late autumn, dried and utilised as an expectorant (to promote discharges of mucus, etc., from the lungs or throat), to increase excretion of bile (A bitter, alkaline, brownish-yellow or greenish-yellow fluid that is secreted by the liver, stored in the gall-bladder, and discharged into the duodenum and aids in the emulsification, digestion,and absorption of fats. Also called gall).
Besides these aspects, the medicinal root is also slightly laxative (aperient, gently stimulating evacuation of the bowels).
It has also been utilised as a vermifuge (anthelmic) capable of causing the evacuation of parasitic intestinal worms.
Young leaves which were dried in shade have also medicinal value for healing asthma, bronchitis (inflammation of the bronchial tubes, characterized by coughing, difficulty in breathing, etc., caused by infection or irritation of the respiratory tract) and rheumatic disorders.
Leaves were known also to be utilised as a bathing medium.
Botanical description: (not perfect, check from local botanists)
Rhizome is horizontal, long and somewhat bold. Leaves are 15-35cm tall and are located individually or few of them can also be connected to each another (see the picture of advertisement of jaani’s festival in Aizpute). The leaves stay green over the winter. Sporagniums are clustered as sorus under the leaf blades and are round shaped, without indusiums (scaly tissue covering the sorus). This fern thrives in cracks of rock, and on stones in the forest and is also rarely found at the base of trees.
Pteridium aquilinum (Eupteris aquilina)
This fern has a Finnish folkname referring to a dead one’s grasp. In times of famine the root of this fern was utilised as a coffee substitute after roasting.
The root is rich in starch and protein, and therefore it was also dried and ground for addition into the baking flour, porridges and pancakes.
The root contains some astringent substances (karvasaine), which are necessary to remove from the flour through a special process: The flour is carefully mixed in container with twice the amount of water and after the flour has settled into the bottom of the container – the remaining water is discarded; this is repeated 3-4 times and then the washed flour is dried for utilisation.
The root of this fern is also utilised in special beer-alike drink, which is fermented from the starch of the root.
In the spring-time the young approximately 5-15 cm tall shoots are utilised for food after boiling in brine (salted water) and eaten like asparagus. In Japan this type of food is called as “Warabe”.
The harvest season in Finland comes after Matteuccia struthiopteris has finished.
It must be noted that the fresh plant contains an enzyme called thiaminase, which will eventually cause deficiency of vitamin B1 if ingested. This enzyme can also develop a stomach cancer for humans if eaten in quantity. However, if these delicate shoots are properly boiled and eaten in moderate amounts with, for example, white sauce and butter, there is no health hazard for humans. It is known that fully developed leaves of this fern have caused poisonings for cattle if used as a forage.
Dried stem of the mature leaves are suitable for twining as those are very stirdy.
Botanical description: (not perfect, check with local botanist)
Rhizome is horizontal and long. The leaves are located individually: Rig is 30-150 cm long and leaf blades are 25-60 cm tall, hard, triangular shaped and 2-3 times pinnate. The underside of the leaf-blade is hairy and topside is bald. Clusters of sporagnia form a continuous belt on the underside of the leaf-blades, sheltered within the leaf margin, which is somewhat bent to the underside of the leaf-blade. This fern thrives in moist and dry sparsely wooded forests, in forest-pastures, in areas left by forest fires, in clearcuts and on roadsides, and fertile flooded forests alongside small streams.
Matteuccia struthiopteris (Struthiopteris filicastrum)
This fern is obviously not as poisonous as other ferns. It’s finnish name “kotkansiipi” translates into a wing of an eagle, due to it’s shape. In the springtime the young shoots which have not yet opened their leaves are utilized for food after boiling in brine (salty water) for 10-15 minutes.
Those are eaten like asparagus or mixed in salads. In some of the states of USA and in Canada it is possible to buy frozen or otherwise preserved springshoots from supermarkets all the year round.
Botanical description (not perfect, check from local botanists):
Rhizome of this fern is short, erect and with stolons. Leaves are fronds which do not have sporangiums and are 30-150 cm tall, erect and form a funnel-like bunch (harvests water). These sterile fronds taper abruptly towards the top, and very gradually towards the base. Ribs are extremely short and leaf-blades are 1-pinnate-pinnatifid. The sporagniums are located in erect sporophyls of separate fertile fronds, which are dense and rigid, first green and maturing to
dark brown (could be associated with flower?). Sporophyls are much shorter and more narrow than infertile fronds. Sporagniums are coated with indusiums. Fertile fronds stay erect over the winter and make it relatively easy to identify in early spring. This fern thrives in fertile edges of small streams, fern-groves, wet groves, flood plains, and is also grown as an ornamental plant in gardens.
Dryopteris filix-mas (Aspidium filix-mas), male fern
and D. dilata, D. carthusiana, D. expansa, D. cristata, D. fragrans
These are poisonous ferns, which have in the past been utilised as a medicine for human intestinal worm (Diphyllobothrium latum).
This medicine should not in any case be utilised on DIY-basis as even a slight overdose can cause a serious poisoning.
All the ferns belonging to family Aspidiaceae contain many poisonous substances, especially in the lower part of the stem and in the roots. The most research has been conducted on male fern (Dryopteris filix-mas) and the symptoms of poisoning are described as following:
Filix-acid is effect on stomach and intestines and after absorption it for first stimulates central nervous system, but will right after cause it’s paralysis. It will also cause nausea, vomiting, cramps in the stomach and diarrohea.
Strong dosage will cause unconsciousness, strong tetanus-like cramps, weakness in heart, breathing problems, liver damage, jaundice and usually (but not always) transitory or permanent blindness in one or both of the eyes due to retinal damage.
Extremely strong poisoning will cause death due to paralysis of respiratory and cardiovascular organs.
Early descriptions of medicinal usage of these ferns are described by Teofrastos in 3th century BC. The roots of D. filix-mas and D. carthusiana were utilised as a vermifuge for intestinal worms and ashes of these among the other ferns were utilized in soap making.
Botanical description: (not perfect, check from local botanists)
Rhizome is short, somewhat erect or horizontal, often coated with dense scales (somehow similar to lizards or fish). Leaves are fronds and form a bunch. Leaf-blades are 1-3 pinnate, ribs are scaled and so are often the mid-ribs. Sporagniums are clustered in round groups and are coated with kidney-shaped indusiums.
The family Dryopteridaceae also contains more species including:
Polystichum sp., Diplazium sp., Athyrium sp., Cystopteris sp., Gymnocarpium sp. and Woodsia sp.
Some other ferns not mentioned here include:
Ophioglossaceae sp., Botrychium sp., Cryptogramma sp., Thelypteris sp., Phegopteris sp.,
Maybe also some other species are known in Latvia?
Luonnontieteellinen keskusmuseo, Kasvimuseo, Helsinki 1998
Botanian tietolaari 9: Myrkkykasvit,
Anna Kokkonen & Markku A. Huttunen
Joensuun yliopistopaino, Joensuu 2001
Luonnonvaraiset hyöty- ja myrkkykasvit,
Turkka Aaltonen & Nalle Corander, 1997