Mr. Walter Roberts read a paper on “Insects injurious to Agriculture,” of which the following is an abstract: –

“Among the many difficulties that beset the agriculturist in the cultivation of his crops, one of the most serious is that arising from the attacks of insects. A very rudimentary knowledge of Entomology reveals the fact that an innumerable host of small, but most voracious and terribly destructive, enemies are constantly attacking every green thing, so that the wonder is how any vegetation escapes and comes to perfection at all. Any information, therefore, respecting their appearance, habits, and methods of attack, also how their ravages may be prevented or lessened must be of the utmost value to the farmer, and a subject of great interest to the public generally.

Beetles are among the more destructive of our farm pests, and of this order the click-beetle or ‘skip jack’ (so called from its power of regaining its feet with a spring or skip, accompanied with a sharp click) and whose larva is the terrible wireworm, may be taken as type. This small worm. In shape and colour like a piece of flattened wire, inflicts incalculable damage upon every kind of grain and root crop. When feeding, it glides about just beneath the surface of the soil, gnawing the roots and underground shoots, and, as its habit is to go from plant to plant, it injures and destroys far more than it needs for food. Unlike most insects, it lives on as a grub for several years, feeding all the time. To prevent their ravages, everting should be done to prevent the beetle laying its eggs, and to clear infected land before sowing. In the case of seeds (one main starting point of attack), the practice of penning sheep them is a most effectual, as the ground becomes so thoroughly trodden and manured that the beetle is prevented depositing her eggs, and if any are already there they are destroyed. Paring and burning the surface and burning the parings will also get rid of a great deal of wireworm. Dressing pastureland with lime brought fresh from the kiln is also very useful, and salt sown upon grass or seeds before breaking up is strongly recommended. The point of most importance is to clear the ground of all weeds and rubbish, as they are the natural homes and harbours of the worm. Land not well cleaned, and where the common and pernicious practice is followed of allowing grass headlands and broad strips of grass by hedge sides, there will be wireworms, as both food and lodging is provided till the crop is ready for them.

Moles are their natural enemies, when burrowing they are brough into their feeding ground and destroy large numbers. Whether the benefit derived from their presence does not far outweigh the damage down is a question the farmer would do well to think over before engaging the service of the mole catcher.

The turnip flea beetle, commonly called ‘The fly’ is another variety doing most serious damage to our turnip crops. In this case, the beetle itself does the mischief – devouring the leaf and quickly destroying the young plant. It passes the winter under clods of earth, stones, and in growths od neglected grass. And by doing away with these, you clear them out of winter quarters. Again, when they come forth in the early spring there are no turnips, and they need food – this is, too often provided in abundance by the rich growths of weeds on many farms, Charlock, commonly known as ‘Ketlock’, is a favourite food. The best method of prevention is – no weeds. Starve them out by destroying their food plants – ‘Prevention is better than cure.’ It is the worst possible practice to wait for the attack and then work directly upon the insect. The object should always be to prevent it.

The Crane fly, or ‘Daddy Longlegs,’ in its larvae state is a most injurious insect. It is known as the ‘Leather Jacket,’ from the roughness of its skin, and, like the wireworm, it feeds upon the underground shoots of root and corn plants; it also comes up above the surface during the night and feeds upon the stems of growing crops. Rolling in the early morning will destroy many, for they are so numerous that 200 have been counted on a square yard of land. Flooding the land is sometimes resorted to in extreme cases, also the use of strong chemicals, as nitrate of soda and carbolic acid. But experiments have shown that they will bear immersion for several days and live, and that if chemicals are used of sufficient strength to destroy the insect, the injure the crop. Frost, too, will not kill them, as after being frozen by artificial means till brittle, when thawed they have been found alive. The same methods of prevention should be used as in the wire worm attack, and, in addition, every means employed by good drainage to avoid wet and marshy places, as these are the resorts of the Crane fly, when she lays her eggs and where attack commences.

Another fly of the gnat tribe, the tiny wheat Midge, does immense damage by depositing its eggs in the florets of the wheat, from which are produced the ‘red maggot,’ which devours the germ of the future grain, producing barrenness and sterility. When full grown, some of the maggots go down into the ground, and they may be destroyed by deep ploughing, which places such a thickness of earth upon them that they are killed, or the perfect fly cannot come up again. Many are housed with the grain, and are to be ground in multitudes in heaps of chaff, which should in no case be allowed to lie about, but should be destroyed.

The turnip Saw fly produces the grub known as ‘The Nigger,’ from its colour, and whose voracious appetite and countless numbers will frequently clear the turnip crop from the face of the earth. The farmer’s only hope in this case is in prevention by the means already recommended, as their numbers cannot be coped with when attack has commenced.

Much excitement has recently been caused by reported appearances of Hessian fly. This is no new insect, but first appeared in England in 1776, and its derived name from the idea that it was brought over by the Hessian troops in the straw from Germany. It then did enormous damage to wheat crops by perforating the main stem and depositing its eggs, causing it to droop and die.

The small insects called Aphids, or plant lice, do immense damage not only to choice plants and flowers, but to grain and root crops as well. The ‘honey dew’ is an excrescence exuded from two small tubes with which they are furnished, and which, by clogging the spores of plants, clogs and smothers them. They posses, also, a powerful beak or sucker, with which they pierce the ears of wheat, and by sucking out their juices do great injury to the crop, The great difficulty of dealing with them is their amazing power of reproduction, it being estimated that one female will be progenitrix of 5.900, 000, 000 aphids in one season. Where field crops are attacked the evil cannot be coped with, but in garden cultivation much may be done by washings of soap suds, tobacco water, and soft soap and quassia.

There is no doubt that immense benefit is derived from the unceasing war carried on by birds upon every kind of insect life. The rook, the pewit, and the starling destroy untold numbers of wireworms, caterpillars, and slugs. Whilst almost every kind of small bird – the sparrow, perhaps, excepted – prays upon aphids, grubs, and other small insects. There can be little doubt that the practice of destroying birds whenever possible is a suicidal policy, the balance of nature being thereby destroyed. An eminent authority says: – ‘If we increase the quantity of any special crop so as to attract any special insect, and at the same time allow the birds which feed upon them to be destroyed, we can hardly fail to suffer severely.’”