SilverweedBotanical Name: Potentilla anserina (LINN.)
Family: N.O. Rosaceae
Synonyms: Prince's Feathers. Trailing Tansy. Wild Agrimony. Goosewort. Silvery Cinquefoil. Goose Tansy. More Grass. Wild Agrimony.
Part Used: Herb.
The Silverweed, one of the commonest of the Potentillas, is very abundant in Great Britain and throughout the temperate regions, extending from Lapland to the Azores, and is equally at home in regions as remote as Armenia, China, New Zealand and Chile.
All soils are congenial to its growth. It spreads rapidly by means of long, creeping runners and thrives in moist situations, especially in clay, where the water is apt to stagnate, and is common by waysides, though on dusty ground it becomes much dwarfed.
It has a slender, branched root-stock, dark brown outside, which has been eaten in the Hebrides in times of scarcity.
The leaves are covered on both sides with a silky, white down of soft hairs, mostly marked on the underside, hence its English name of Silverweed. They are 2 to 5 inches long, much cut or divided, interruptedly pinnate, i.e. divided into twelve to fifteen pairs of oval, toothed leaflets along the midrib, each pair being separated by a shorter pair all the way up.
The buttercup-like flowers, in bloom from early summer till later autumn, are borne singly on long footstalks from the axils of the leaves on the slender runners. They are large, with five petals of a brilliant yellow colour and the calyx is cleft into ten divisions.
The Silverweed is a favourite food of cattle, horses, goats, pigs and geese. Only sheep decline it.
Older writers call it Argentina (Latin, argent, silver) from its appearance of frosted silver. The name Anserina (Latin, anser, a goose) was probably given it because geese were fond of it.
The generic name, Potentilla, is derived from the Latin adjective potens, powerful, in allusion to the medicinal properties of some of the species.
Parts Used: All parts of the plant contain tannin.
In modern herbal medicine the whole herb is used, dried, for its mildly astringent and tonic action. It has an astringent taste, but no odour.
The roots, which are even more astringent, have been used, also the seeds.
The herb is gathered in June, all shrivelled, discoloured or insect-eaten leaves being rejected. Collect only in dry weather, in the morning, after the dew has been dried by the sun. Failing the convenience of a speciallyfitted drying-shed, where drying is carried on by artificial heat, drying may be done in warm, sunny weather out of doors, but in half-shade, as leaves dried in the shade retain their colour better than those dried in the sun. They may be placed on wire sieves, or wooden frames covered with wire or garden netting, at a height of about 3 or 4 feet from the ground, to ensure a current of air. The herbs must be brought indoors to a dry room or shed at night, before there is any chance of them becoming damp by dew.
For drying indoors, a warm, sunny attic may be employed, the window being left open by day, so that there is a current of air for the moist, hot air to escape; the door may also be left open. The leaves and herbs can be placed on coarse butter-cloth, stented, i.e. if hooks are placed beneath the window and on the opposite wall, the butter cloth can be attached by rings sewn on each side of it and hooked on so that it is stretched quite taut. The temperature should be from 70 degrees to 100 degrees F. Failing sun, any ordinary shed, fitted with racks and shelves can be used, provided that it is ventilated near the roof, and has a warm current of air, caused by an ordinary coke stove or anthracite stove. The important point is rapidity and the avoidance of steaming; the quicker the process of drying, the more even the colour obtained, making the product more saleable.
All dried leaves should be packed away at once in wooden or tin boxes, in a dry place, as otherwise they re-absorb about 12 per cent of moisture from the air, and are liable to become mouldy and to deteriorate in quality.
Medicinal Action and Uses: A strong infusion of Silverweed, if used as a lotion, will check the bleeding of piles, the ordinary infusion (1 OZ. to a pint of boiling water) being meanwhile taken as a medicine.
The same infusion, sweetened with honey, constitutes an excellent gargle for sore throat. A tablespoonful of the powdered herb may also be taken every three hours.
It is also an excellent remedy for cramps in the stomach, heart and abdomen. In addition to the infusion taken internally, it is advisable to apply it to the affected parts on compresses.
On the Continent, a tablespoonful of the herb, boiled in a cup of milk, has been recommended as an effective remedy in tetanus, or lockjaw. The tea should be drunk as hot as possible. If the patient dislikes milk, boiling water may be used.
The dried and powdered leaves have been successfully administered in ague: the more astringent roots have been given in powder in doses of a scruple and upwards.
As a diuretic, Silverweed has been considered useful in gravel. Ettmueller extolled it as a specific in jaundice. Of the fresh plant, 3 OZ. or more may be taken three or four times daily.
The decoction has been used for ulcers in the mouth, relaxation of the uvula, spongy gums and for fixing loose teeth, also for toothache and preserving the gums from scurvy.
A distilled water of the herb was in earlier days much in vogue as a cosmetic for removing freckles, spots and pimples, and for restoring the complexion when sunburnt.
In Leicestershire, Silverweed fomentations were formerly used to prevent pitting by smallpox.
Salmon (1710) says:
'It is very cold and dry in the second degree, astringent, anodyne, vulnerary and arthritic. It stops all fluxes of the bowels, even the bloody flux, also spitting, vomiting of blood, or any inward bleeding. It helps the whites in women and is profitable against ruptures in children and is good to dissipate contusions, fastens loose teeth and heals wounds or ulcers in the mouth, throat or in any part of the body, drying up old, moist, corrupt and running sores. It resists the fits of agues, is said to break the stone, and is good to cool inflammation in the eyes, as eke to take away all discolourings of the skin and to cleanse it from any kind of depredation.'