WIREWORM. The Editor is indebted to Dr Spencer Cobbold, F.R.S., for the following communication on this subject:—“Dear Prof. Tuson,—You asked me about the remedies for wireworm. Although a great deal has been said on the subject, yet it is not easy to advise. I believe the best plan is to ‘catch-’em-alive’ by means of sliced potatoes, turnips, or carrots laid in rows, women and children being employed every morning to pick up the slices, and brush off the larvæ into a jar (the slices being replaced). Mr Hogg (the Ettrick Shepherd) found lettuce leaves very serviceable when laid as a bait in a similar way. Pheasants are very destructive to them. As agriculturists do not like the trouble and expense of this baiting method (by far the best if persevered in) some have recommended deep ploughing, &c. The following extract taken from the ‘Journal of the Agricultural Society, of Victoria,’ bears on the question at issue. Trusting it may be found useful, believe me, yours faithfully, T. Spencer Cobbold.”
“Remedy for Wireworm.—Having seen in your issue of the 24th ult. that ‘B,’ would be glad if any one could give any information as to a remedy for the ravages of the wireworm, which plays such havoc in our corn fields during the early part of the growth of
our cereal crops, I beg to offer a few observations on the subject. I have for years paid particular notice as to any remedy or preventive, and it is with regard to the latter that I shall chiefly confine my remarks, as there is positively no known remedy when once the insects have attacked the crop. Some persons recommend the application of lime or salt, but it is a well-known fact that if either of these is applied in such quantity as to destroy the worm, it will likewise destroy vegetation, and consequently the crop will be entirely lost; and not alone this crop, but the soil will be poisoned to such an extent as to injure succeeding crops. What I have found most successful is deep ploughing, not what is ordinary called deep ploughing, 7 or 8 inches, but to the depth of at least 10 or 12, where the soil will admit of it. The wireworm lives not more than 4 inches below the surface, and by burying it 10 or 12 inches it is found that it cannot again make its way to the surface, and consequently can do no injury to surface-rooted plants, such as the grain crops. The operation of ploughing should be performed as follows: a strong skim coulter is attached to the beam of an ordinary strong plough, which is drawn by three horses. The skim coulter pares off the surface, which is buried underneath the sod turned over by the mould-board. Or it is sometimes performed in a different way. A small plough, drawn by one horse, precedes the ordinary plough, skimming off the surface exactly the same as the skim coulter. So much for a preventive. As to remedy, what I have found most effectual is heavy rolling, using, if possible, such a roller as that called the Crosskill, which crushes the insects, killing some, and preventing others doing much damage until the crop is sufficiently far advanced as not to be affected by the insect.—John Thomas, 32, Capel Street, Dublin.”
WITCH MEAL. Syn. Vegetable sulphur, Lycopodium. The spores of Lycopodium clavatum, or club moss.
WOAD. Syn. Dyer’s woad; Pastel, Fr. The Isatis tinctoria. To prepare them for the dyer, the leaves are partially dried and ground to a paste, which is made into balls; these are placed in heaps, and occasionally sprinkled with water, to promote the fermentation; when this is finished, the woad is allowed to fall down into lumps, which are afterwards reground and made into cakes for sale. On mixing the prepared woad with boiling water, and, after standing for some hours in a closed vessel, adding about 1-20th its weight of newly slaked lime, digesting in a gentle warmth, and stirring the whole together every 3 or 4 hours, a new fermentation begins; a blue froth rises to the surface, and the liquor, though it appears itself of a reddish colour, dyes woollens of a green, which, like the green from indigo, changes in the air to a blue. This is said to be one of
the nicest processes in the art of dyeing, and does not well succeed on the small scale. Woad is now mostly used in combination with indigo. 50 lbs. of woad are reckoned equal to 1 lb. of indigo.
WOL′FRAM. See Tungsten.
WOLFS′BANE. See Aconite.
WOOD is polished by carefully rubbing down the grain with fine glass paper, or pumice-stone, and then rubbing it, first with finely-powdered pumice-stone and water, and afterwards with tripoli and linseed oil, until a proper surface is obtained. For common purposes, glass paper, followed by a metal burnisher, is employed.
Wood is stained by the application of any of the ordinary liquid dyes employed for wool or cotton. They sink deeper into the wood when they are applied hot. When the surface is properly strained and dried, it is commonly cleaned with a rag dipped in oil of turpentine or boiled oil, after which it is either varnished or polished with beeswax. Musical instruments, articles of the toilette, &c., are usually treated in this way.