grass and corn land. Great care ought, therefore, to be taken not to disturb these birds, especially as in fallowed lands, where grubs generally abound, they are of infinite service. In this case, the land should be stirred with the plough as often as the weather will permit; for, if the rooks once find their way thither, they will not abandon the plough, unless driven away by violence; and each time the land is stirred, they will destroy multitudes of these vermin. Were this the only advantage to be derived from their destruction, it would amply compensate the farmer for the labour and expence bestowed upon it. Independently of the beneficial effect, which this management produces on the fertility of fallow-land, it may frequently be attended with the destruction of a whole race of grubs, in the adjacent fields.
But, as this method is impracticable in gardens, recourse ought to be had to other expedients. Gardeners have observed that cabbages, cauliflowers, strawberries, and especially lettuces, are the favourite food of the grub. In order to destroy that pernicious insect, they plant a row of lettuces between the rows of strawberries, in which case the insect will preferably attack the former. Hence, they carefully examine the plants every day, walking along the rows with a trowel: wherever they observe leaves falling, they know their enemy is on the spot; immediately dig it up, and thus destroy the grub.
The whole race of these insects may probably be extirpated in stiff soils, by long continued rains, during the winter. For at that time, they having descended deep into the ground, the passage must be in some measure left open, so as to allow the water, if in abundance, to soak down to the bottom of their hole; which, in a retentive soil, it will fill, and, if continued a sufficient time, infallibly drown them. Wherever irrigation is employed for other purposes, the extermination of the grub may be effected by this method; and there are many situations, in which water may be commanded in quantities adequate to this important purpose. It is highly probable that, if a stream of water could be spread over the surface of a grass-field, only for a few days, during any of the winter or spring months, all the grubs might be drowned in their holes: and as water is most abundant in that season, a very small stream might be so conducted, in different directions, as to inundate a large tract of ground. The benefit of one irrigation, thus managed, would be felt for five years. We therefore venture, with Dr. Anderson, to recommend this mode of destroying grubs, to those who have grass-lands infested with them; especially when they are intended to be converted into corn-land; for the injury done by grubs to the first crop, is often severely felt. It might even be safely applied to orchards, and wood-lands, provided that the water were not continued longer than is necessary to effect the destruction of the worms.
Having thus given a succinct analysis of the different methods of exterminating the cock-chafer, in its earlier stages of existence, suggested by native writers, we proceed to lay before our readers the latest discoveries made on the Continent, relative to this important subject.
