Herb: Narrow Buckler Fern

Latin name: Dryopteris carthusiana

Synonyms: Aspidium spinulosum, Dryopteris spinulosum

Family: Dryopteridaceae (Wood Fern Family)

Medicinal use of Narrow Buckler Fern:

The root contains "filicin", a substance that paralyses tapeworms and other internal parasites and has been used as a worm expellent. It is one of the most effective treatments known for tapeworms - its use should be immediately followed by a non-oily purgative such as magnesium sulphate in order to expel the worms from the body. An oily purge, such as caster oil, increases the absorption of the fern root and can be dangerous. The root is harvested in the autumn and can be dried for later use, it should not be stored for longer than 12 months. This remedy should be used with caution and only under the supervision of a qualified practitioner. The root is toxic and the dosage is critical. See also the notes above on toxicity.

Description of the plant:


100 cm
(3 1/4 foot)

Habitat of the herb:

Damp and wet woods, marshes and wet heaths.

Edible parts of Narrow Buckler Fern:

Root - baked. Some caution is advised, see notes above on toxicity. Old leafstalks on the underground stems can be roasted, peeled and the inner portion eaten. Young curled fronds, harvested as they are developing in the spring, can be boiled and eaten like asparagus.

Other uses of the herb:

When spaced about 30cm apart each way, the plants can be grown as a ground cover.

Propagation of Narrow Buckler Fern:

Spores - can be sown at any time of the year in a greenhouse. Surface sow on a sterilised compost and keep moist, possibly by placing the pot in a plastic bag. Germinates in 1 - 3 months at 20C. Pot up small clumps of the plants when they are large enough to handle and grow on in a shady part of the greenhouse until large enough to plant out. Division in spring. Larger clumps can be replanted direct into their permanent positions, though it is best to pot up smaller clumps and grow them on in a cold frame until they are rooting well. Plant them out in the spring.

Cultivation of the herb:

Damp and wet woods, marshes and wet heaths.

Known hazards of Dryopteris carthusiana:

Although we have found no reports for this species, a number of ferns contain carcinogens so some caution is advisable. The fresh plant contains thiaminase, an enzyme that robs the body of its vitamin B complex. In small quantities this enzyme will do no harm to people eating an adequate diet that is rich in vitamin B, though large quantities can cause severe health problems. The enzyme is destroyed by heat or thorough drying, so cooking the plant will remove the thiaminase. However, there have been reports for other species of ferns suggesting that even cooked fronds can have a long term harmful effect. Some caution is therefore advised.

Plant information taken from the Plants For A Future.