Marginal Woodfern, Leather Wood Fern
Dryopteris marginalis
Family: Dryopteridaceae
What it is like
Form: Irregular or sprawling, Spreading or horizontal, Upright or erect.
Dryopteris marginalis is an evergreen Fern growing to 0.8 m (2ft 7in) by 0.3 m (1ft) at a medium rate. See above for USDA hardiness. It is hardy to UK zone 4. It is in leaf all year. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils. Suitable pH: mildly acid and neutral soils. It can grow in semi-shade (light woodland). It prefers moist soil and can tolerate drought.
Height (m): 0.8
Where it is found
Damp woods and swamps. Rocky, wooded slopes and ravines, edges of woods, stream banks and roadbanks, and rock walls at elevations of 50 - 1500 metres.
N. America - Canada to Georgia and westwards to the Rockies.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 0
Medicine
Rating: 4
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. An infusion of the root has been used in the treatment of rheumatism. A warm infusion, held in the mouth, has been used to treat toothaches.
Antirheumatic: Treats rheumatism.
Odontalgic: Treats toothache (temporary measure only) and other problems of the teeth and gums.
Vermifuge: Expels and kills internal parasites.
Other
Rating: 0
Food Forest: Plants for Edible Forest Gardens and Food Forests.
How it is grown
Landscape Uses:Container, Ground cover, Specimen, Woodland garden. Prefers an acid to neutral soil, succeeding in ordinary fertile soil in a shady position. Succeeds in full sun but grows best in a shady position with only 2 - 3 hours sun per day. Tolerates a pH range from 4.5 to 7. Dislikes heavy clay. Prefers a good supply of water at its roots but succeeds in dry shade and tolerates drought when it is established. A very hardy plant, tolerating temperatures down to about -30°c. Members of this genus are rarely if ever troubled by browsing deer. Hybridizes in the wild with several other species. Special Features: Attractive foliage, North American native, Wetlands plant, There are no flowers or blooms. The plant is heat tolerant in zones 8 through 1. (Plant Hardiness Zones show how well plants withstand cold winter temperatures. Plant Heat Zones show when plants would start suffering from the heat. The Plant Heat Zone map is based on the number of "heat days" experienced in a given area where the temperature climbs to over 86 degrees F (30°C). At this temperature, many plants begin to suffer physiological damage. Heat Zones range from 1 (no heat days) to 12 (210 or more heat days). For example Heat Zone. 11-1 indicates that the plant is heat tolerant in zones 11 through 1.) For polyculture design as well as the above-ground architecture (form - tree, shrub etc. and size shown above) information on the habit and root pattern is also useful and given here if available. An evergreen. The plant growth habit is a clumper with limited spread. The root pattern is rhizomatous with underground stems sending roots and shoots along their length.
Propagating it: 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 20°c. 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.
Best place to grow: Woodland Garden Dappled Shade; Shady Edge;
Habit: Fern
Hardiness: 3-8
Growth: Medium
Soil: Light (sandy), medium, heavy (clay)
Shade: Semi-shade
Moisture: Moist
Things to keep in mind
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.