72 On the Means of preventing 



1. Slugs. These are properly " naked snails." They abound in 

 spring, but only appear early in the morning 1 , and late in the_evening, 

 more especially when the weather is warm. Jn the day time, they destroy 

 the roots, and in the night, the blades, and other parts of the young 

 wheat which they find above ground. They deposit their eggs in the 

 earth. Powdered salt, saltpetre, and quicklime, are destructive to slugs ; 

 but lime-water is the most effectual, the least drop of it killing them. 

 For that purpose, some diligent farmers collect them by means of pea- 

 haulm, under which they shelter themselves, and they are then de- 

 stroyed by a watering pot, by means of which, lime-water is sprinkled 

 over them, when the haulm is removed. Sulphuric acid, even diluted, 

 would probably answer the same purpose. Rolling the ground at 

 night, or treading the surface with sheep, &c. are useful practices for 

 the destruction of this species of vermin. 



2. Grubs. These are worms or maggots produced from the eggs 

 of beetles, which ultimately are transformed into winged insects of the 

 same species as their parent. They are likewise called " the rook 

 worm" rooks being so fond of them. They do great injury to the 

 crops of grain, by undermining and feeding upon the roots of the 

 plants. They are hardy in their egg state, and, when grubs, are in- 

 vulnerable to the weather ; but when passing from the aurelia state, 

 rain and cold weather will destroy them. This maggot is so destruc- 

 tive, that if every season were equally favourable to its production, it 

 would soon render the world a desert. 



Various remedies have been recommended for destroying them, in 

 particular, sowing salt with the seed, strewing barley chaff on the 

 surface, so as to entangle and destroy them, spreading quicklime, 

 or saltpetre over the field, before the plants get up, employing ducks 

 to devour them, rolling the earth, more especially during the night, 

 when the grubs are generally on the surface, and treading the sur- 

 face with sheep or pigs, and sometimes even with horses. 



3. The Wire-worm. This is a noxious animal, abounding both in 

 old grass -lands, and in clover leys. It is very difficult to destroy them, 

 as they are peculiarly tenacious of life. For five years, the wire- 

 worm remains inhabiting the earth, till it changes its nature, and be- 

 comes a winged fly, (the Elator segetis of Linnaeus) *. Some recom- 

 mend, as the surest and most effectual means to get rid of them in 

 old grass lands, to pare and burn the surface. Others suggest the 

 sowing of spring instead of winter wheat, on the idea that the culture, 

 at that season of the year, would destroy them. A plan has recently 

 .been suggested by Mr Radcliffe, an intelligent clergyman in Ireland, 

 of paring the surface of old leys, accumulating it in great heaps in 

 the fields, and planting the field, and even the heaps with potatoes. 

 By this means, a valuable crop is raised, the destruction of the 

 wire-worm is insured, and an immense quantity of valuable earth, full 

 of rich substances, is obtained. Another effectual mode of destroying 

 the wire-worm is, to plough the clover stubble in July, as soon as the 

 crop of hay is taken off, or the land has been cut for soiling, and then 



* See Trans, of the Linnaean Society, vol. ix. p. 160. 



