This weed is extremely difficul to be eradicated, as its roots, in soft and deep soils, have been found at the depth of eight feet. One of the most effectual methods of extirpating the fern is, to mow the grass frequently; and, if the field be ploughed up, and well dunged, this plant will not thrive : - urine is said to be of considerable efficacy in checking its vegetation. It may also be easily destroyed, by means of an instrument consisting of a stick, in which is inserted a blade, with blunt edges, and with which the stems of the plant are to be bruised. Several acres may thus be cleared, even by a woman, in the course of one day: the next morning a gummy matter will exude from the injured stalk, and the fern will gradually disappear.
But, however troublesome tills vegetable may prove to the industrious husbandman, it is not altogether useless, and might well deserve to be regularly cultivated in those places where few other vegetables will grow.
For covering the roofs of houses, fern affords a valuable substitute for straw : in order to apply it to this useful purpose, it should be pulled up together with its roots, in the beginning of October, when it is perfectly pliant, and not liable to break : if these precautions be attended to, the thatch will continue sound for thirty years. It also produces excellent litter for horses and cows; and when dry, is eaten by cattle, for which purpose it should be cut from the middle of August to that of September. Hogs are particularly fond of its roots, which render them exceedingly fat; and, it has been found by experience, that, if the stalks be scalded for a few minutes, and mixed with bran, for store hogs, half the quantity of bran will be saved ; so that from February to June these animals may be kept at one half of the expence, by a weed growing abundantly on waste lands. It ought, however, to be remarked, that young pigs should not be fed with this plant, as it is naturally too heating for them, and might be productive of dangerous consequences.
Fern may also be employed as an excellent manure for potatoes: fcr, if it be buried beneath the Trots of the latter, it seldom fails to produce a good crop. - It is likewise a proper substitute for coal, where the latter is scarce, for the various purposes of brewing, baking, heating ovens, and burning lime-stone, as it emits a powerful heat.
The ashes of fern, when burnt, are frequently used by the manu-facturers of glass, especially in France, because they afford a tolerably pure alkali. - In several parts of Britain, the poorer class of people mix these ashes with water, and form them into round masses, which they call fern-balls: these are next heated in a fire, before they are made into a lye for scow-ering linen. M. Friewald observes, in the 4th volume of the Transactions of the Swedish Academy, that his countrymen mix the fern ashes with a strong lye, previously to forming them into balls, and afterwards dry them: thus, a very cheap substitute is prepared for soap; and the linen washed with it, not only becomes perfectly white, but is at the same time free from that disagreeable smell, frequently contracted by linen imperfectly washed with the common soap. - According to Prof.
Beckmann, fern produces the 9th part of its original weight, when burnt to ashes; and Scheffer, in his Chemical Lectures, published in German, remarks, that it yields the largest proportion of ashe9 among all known vegetables. M. Gmelin even affirms, that it affords no less than the third part of its own weight in vegetable alkali.
Beside the multifarious uses to which the fern is subservient, it. may be applied to a purpose still more important. In the "Me-moirs d'Agriculture," for 1786, we find that this vegetable furnishes the inhabitants of Palma, one of the Canary isles, with their daily bread: in digging for its roots, they first taste them, and reject those which are bitter, as useless. Such facts require no commentary.
the Male Fern, , or Male Polypody, Polypodium Filix-mas, L. is an indigenous plant growing in woods, heaths, and stony places, and flowering from June to October.
This vegetable has nearly the same qualities, and is used for the same purposes as the female fern. In Norway, the dried leaves are infused in hot water, in which state they afford a wholesome food to goats, sheep, and other cattle, which eat them eagerly, and sometimes grow fat by their constant use. - The inhabitants of Siberia boil the male fern in their ale, on account of the flavour which it imparts to that liquor. The roots, when pulverized, are an excellent vermifuge, and have been given with great success, in the proportion of two or three drams, for the expulsion cf the taenia, or tape-? worm.