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Common Name: Sweet Fern

General Information

Comptonia peregrina asplenifolia is a deciduous shrub that can grow up to 1.20 metres tall.
It is harvested from the wild for local use as a food, medicine and source of materials.

Known Hazards

None known

Botanical References

,

Range

Eastern N. America.

Habitat

Dry, sterile, sandy to rocky soils in pinelands or pine barrens, clearings, pastures or edges of woodlots from sea level to 1800 metres[, ].

Properties

Edibility Rating
Medicinal Rating
Habit	Deciduous Shrub
Height	1.20 m
Cultivation Status	Wild

Cultivation Details

Requires a peaty or light loam lime-free soil[, , ]. Requires an acid well-drained soil of low to medium fertility in partial shade but tolerates full sun if the soil does not dry out in the summer[]. Tolerates dry sandy soils when grown in the shade[].
A very ornamental plant[], it is hardy to at least -25°c[, ]. This form is probably no more than a phenotypic variant of the species that is found growing in harsh conditions[].
The crushed leaves are very aromatic[], their scent is most noticeable in the early morning and the evening[]. The scent increases when the leaves are dried[].
This species is somewhat intolerant of root disturbance and should be planted out into its permanent position whilst small[].
Suckering freely[], this plant is well suited to clothing banks on soils of low fertility[]. It has a symbiotic relationship with certain soil micro-organisms, these form nodules on the roots of the plants and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[].

Edible Uses

The young fruits are eaten as a pleasant nibble[, , ].
The aromatic leaves, fresh or dried, are used to make a palatable tea[, , , ]. The leaves are also used as a seasoning[].

Medicinal

Sweet fern was employed medicinally by several native North American Indian tribes who used it especially as a poultice to treat a variety of complaints[]. It is still used for most of the same purposes in modern herbalism.
The leaves are astringent, blood purifier, expectorant and tonic[, , , ]. A tea made from the leaves and flowering tops is used as a remedy for diarrhoea, headache, fevers, catarrh, vomiting of blood, rheumatism etc[, , ]. The infusion has also been used to treat ringworm[]. The leaves have also been used as a poultice for toothaches, sprains etc[, ].
A cold water infusion of the leaves has been used externally to counter the effect of poison ivy[, , ] and to bathe stings, minor haemorrhages etc[].
The leaves are harvested in early summer and dried for later use[].

Other Uses

The leaves are used as a lining in baskets etc in order to preserve the fruit[].
The crushed leaves repel insects[]. They can be thrown onto a camp fire to keep mosquitoes away[].
The dried leaves have been burnt as an incense[].

Propagation

Seed - it has a very tough seed coat and also contains germination inhibitors and so is very difficult to germinate[]. It is probably best to harvest the seed 'green' (after the seed has fully developed but before it dries on the plant) and sow immediately in a cold frame. If the seed has been stored then soaking in hot water for 24 hours will leach out some of the inhibitors and also help to soften the seed coat. Scarification will also help as will a period of cold stratification. Prick out the seedlings into individual pots as soon as they are large enough to handle. Grow them on in a greenhouse or cold frame for their first winter and plant them out into their permanent positions in late spring or early summer[].
Root cuttings, 4cm long December in a frame[, ]. Plant the root horizontally. High percentage[].
Suckers removed in the dormant season and potted up or planted into their permanent positions[]. Plants can be difficult to move successfully[].
Layering in spring[].