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From this cause the fruit buds are first destroyed, and from the constriction of the bark, they are seldom or ever replaced, so that almost the whole branch remains ever

after barren.

To destroy these vermin, and prevent their depredations, many means have been suggested, such as washing with different liquids. Perhaps a liquid may be found capable of destroying them, and it is not unlikely that plain water may do it; but of this I have no experience; I only make the supposition from always finding their ova in parts of the tree most sheltered from the rain, that is, the inclined side of the trunk, and under side of the horizontal and pendent branches. But the difficulty of application seems unsurmountable, as well as the

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are generally laid so deep and secure in the fissures and crevices, and so completely covered by the bark, that it is impossible to

make any liquid reach them.

Smoaking, tying hair-ropes, &c. round the trees, laying certain substances upon the ground, about the root of the tree, are not

worth taking notice of

As the ova of these insects are lodged in the fissures and crevices of the outer bark, the means I propose to destroy them, is to take off the outer bark completely from the trunk and large branches, as far at least, as it is cracked and scaly, by which they will be effectually dislodged, and must inevitably perish when driven from their nidus. At the same time it will relieve the tree from

the constriction of the dry and hardened bark, which injures its health, and renders it more subject to the attack of vermin; for it is observed that the vermin more readily prey upon the weak and sickly plant, than the more healthy and vigorous: hence it is easy to see how these two causes

act together, to the injury of the tree and

fruit; the one rendering them more subject

to the attack of the other, which carries

them on to total destruction: and it has been

observed that the vermin are more destructive in a cold than in a warm season, which has made some imagine it more favourable to their production; but this is a mistake; the cold is not directly favourable to the production of vermin, but by causing decay of the vegetable which either produces or fosters them. We see this in all putrifying animal and vegetable substances. If the

vermin have penetrated through the inmost bark, it likewise must be cleared away, and the wood scraped round to the sound inmost bark. To facilitate this operation, the small short branches upon the trunk and large branches ought first to be cut away

close to the wood.

It will often happen in young trees, and in older ones where the bark is not cracked by age, that fissures and crevices will be formed by wounds, bystumps of branches decayed or cut off, by the branches rubbing on one another, and perhaps by diseases not well known; one of which, it is not unlikely, is constriction of the bark, for where the outer bark was quite smooth, and apparently sound, I have found the inner and inmost bark diseased. In this case, the diseased part must be entirely cut out, to the wood,

and carried round till you come at sound inmost bark, as in the case of vermin. If the disease penetrate to the wood, and go all round, in the same circle or parallel, that tree or branch has no chance to live, it ought therefore to be cut off. If, however, any part of the wood is fresh, it may be preserved by putting in a piece of fresh bark, from another part of the tree, or from another tree; or it can be preserved by another substance, such as a piece of linen rag, to conduct the sap till a new bark is

generated,

Peeling cannot be of so much service to wall trees, in regard to the vermin, they mostly residing and depositing their ova in

the wall, and not in the bark of the tree;

but it is of equal service in regard to the

constriction.

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