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as to run no risk of being killed by a severe win

ter.

If I should be so fortunate as to induce my readers, once to be satisfied, that it is not an impofsible task to eradicate vermin that are destructive to man, they would soon discover various means of exercising their ingenuity with effect, as soon as they had acquired a competent knowledge of the objects that annoy them. It is, in fact, a much easier task than most persons are aware of: nor is it easy to calculate how much benefit will be in this respect derived from cleanliness and attention alone. There is an insect belonging to this clafs, which has multiplied extremely in the nurseries about this metropolis, and which, unless guarded against, threatens to be extremely destructive to our orchards every where. It lives upon the apple-trees, and, like most of the insects of this kind, throws out such a quantity of cotton-like matter, as sometimes to cover every twig of the young trees as if they had been rolled in cotton, or the down adhering to the willow seeds. The history of this insect is still involved in obscurity; and I believe the changes it undergoes, their periods, and its modes of life during the various stages of its existence, are not distinctly known. Till these be ascertained, however, the most efficacious method of eradicating it cannot be pointed out: and here opens a fine field for the application of genius and industry, which I warmly recommend to such of my young readers as are ambitious of being honourably distinguished among their compatriots. Till this shall be done, I must content myself with premising a few circumstances respecting it, that are not so generally known as they ought to be.

been neglected even till the young are hatched, and have fixed themselves to the leaves, appearing there in great numbers in their scaly state, it may still be effected. In that case, these leaves ought not to be suffered to fall off of themselves, but they should be all carefully plucked off and put into baskets to be carried off the ground. Perhaps the best time for this operation might be as soon as these insects make their appearance upon the leaves; for the tree would soon push out new leaves at that season; but if there be any fruit upon the trees, that operation should be deferred till the fruit be gathered, and then no time should be lost to strip off all the leaves, and brush the young twigs, if any insects shall appear upon them. In this way so few will escape, as to make it an easy matter perfectly to extirpate the remainder by cutting off the females in the spring. By pulling off the leaves at this season too, the vegetation is checked; the points of the young shoots gradually harden before the severe cold of 'winter approaches; and thus they are the better enabled to resist the severity of frost than they otherwise would have been. I have thus, for the sake of experiment, hardened several trees, which, by continuing to shoot late in the season, are apt to have the points of their wings so herbaceous as to be cut down by the mildest winters we ever have, but which, by being thus prepared, have stood our hardest winters without losing a twig. The practice of plucking off the leaves at this season (early in autumn), therefore, is in other respects beneficial, besides that for which it is here recommended, and ought not to be neglected when there seems to be the slightest reason for it. The fig-tree might probably be thus hardened, so

as to run no risk of being killed by a severe win

ter.

If I should be so fortunate as to induce my readers, once to be satisfied, that it is not an impossible task to eradicate vermin that are destructive to man, they would soon discover various means of exercising their ingenuity with effect, as soon as they had acquired a competent knowledge of the objects that annoy them. It is, in fact, a much easier task than most persons are aware of: nor is it easy to calculate how much benefit will be in this respect derived from cleanliness and attention alone. There is an insect belonging to this class, which has multiplied extremely in the nurseries about this metropolis, and which, unless guarded against, threatens to be extremely destructive to our orchards every where. It lives upon the apple-trees, and, like most of the insects of this kind, throws out such a quantity of cotton-like matter, as sometimes to cover every twig of the young trees as if they had been rolled in cotton, or the down adhering to the willow seeds. The history of this insect is still involved in obscurity; and I believe the changes it undergoes, their periods, and its modes of life during the various stages of its existence, are not distinctly known. Till these be ascertained, however, the most efficacious method of eradicating it cannot be pointed out: and here opens a fine field for the application of genius and industry, which I warmly recommend to such of my young readers as are ambitious of being honourably distinguished among their compatriots. Till this shall be done, I must content myself with premising a few circumstances respecting it, that are not so generally known as they ought to be.

Wherever this insect has nestled upon a tree, it communicates a corrosive ichor that affects the tree after the insect itself is removed, like a kind of gangreen; so that the tree becomes blocched, uneven in the bark, and full of deep holes that soon produce its decay and death. The insect fastens itself, by preference, upon the tender buds of young trees, immediately under the axilla of the leaves on the shoots of that year, and very quickly infects them. This insect, however, takes such slight hold, that if it has not had time to bury itself in holes in the bark, it may be easily brushed off by means of a firm dry painter's brush; so that the shoot shall sustain no damage for it. Rain also washes it off from smooth surfaces; and a wet brush may, during moist weather, be efficaciously employed for the same purpose.

Next to the eyes on the young shoot, this insect is found to establish itself in any cavities in the stems or larger branches of trees, which have been produced by tearing off branches incautiously, or any other wound in the bark. In these irregular cavities it finds a protection from rain; and thence, when they are once established, it is difficult to dislodge them by a brush or other mechanical means; so that these cavities may be considered as the nests from which they send out swarms to spread over the young branches when the weather is favourable to them. One great preventive then would be, to scoop out all these cavities to the quick; to cut off all irregular prominences; to scrape off the loose scales from the bark, and then to cover it with Mr. Forsyth's composition, which would not only defend it in the mean time from the operation of these insects, but, by bringing on a smooth clean bark,

would admit of its being washed and cleaned afterwards without difficulty, which would preserve it alike from these insects and many others which find shelter in the inequalities of a rough bark, and give the tree at the same time additional health and vigour.

The above would be the most efficacious mode of proceeding; but those who are too indolent to take this trouble may be benefited by that composition in another way. If a wet mop made of shreads of any sort, or pieces of mat tied up, be dipped in this composition when in a proper degree of fluidity, and then dashed repeatedly upon these irregular cavities where the insect is discovered, varying the direction of the strokes as much as pofsible; the composition is then thrown into every crevice, to which, on account of its cohesiveness, it adheres, so as to envelope the whole insect with a thick coating which, excluding the air, soon makes it perish, and there effectually entombs it. This I have found an easy and efficacious application for exterminating this insect in these its otherwise inaccefsible retreats. All other insects will probably be suffocated for want of air when thus covered. The whole tree, if thus daubed over, would be effectually defended from them for a long time; but in order to cover the small twigs, two mops would be necefsary, which, by being struck against each other with the twig between them, would soon cover it all over. This application, while it kills the insects upon the tree at the time, and guards it against their attacks for a long while after, does not hurt the tree itself. I have found that the aphis also is effectually killed by the same application; and that the leaves and twigs of trees

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