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Common Name:

General Information

Polypodium lineare is a Evergreen Fern up to 0.25 metres tall.
It is harvested from the wild for local use as a medicine..

Known Hazards

Although we have found no reports of toxicity for this species, a number of ferns contain carcinogens so some caution is advisable[].
Many ferns also contain 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[].

Botanical References

Range

E. Asia - China, Japan, Korea.

Habitat

Epiphytic on tree trunks and rocks in lowland and low mountains all over Japan[]. Often found on old brick walls[].

Properties

Medicinal Rating
Habit	Evergreen Fern
Height	0.25 m
Cultivation Status	Wild

Cultivation Details

We have very little information on this species and do not know if it will be hardy in Britain, though judging by its native range it should succeed outdoors in many parts of this country. The following notes are based on the general needs of the genus.
Tolerates short periods of drought and direct sunlight, but it prefers bright filtered light[]. Plants can be grown on a drystone wall[].
Members of this genus are rarely if ever troubled by browsing deer[].

Edible Uses

None known

Medicinal

The whole plant is antiphlogistic and diuretic[, ]. It is used in the treatment of urinary calculus[], urinary tract infections, bacterial dysentery, chronic bronchitis and rheumatism[].

Other Uses

None known

Propagation

Spores - best sown as soon as ripe on the surface of a humus-rich sterilized soil. Keep the compost moist, preferably by putting a plastic bag over the pot. Pot on small clumps of plantlets as soon as they are large enough to handle and keep humid until they are well established. Do not plant outside until the ferns are at least 2 years old and then only in a very well sheltered position.
Division in spring[].