Cultivation of Arable Land. Wheat In/ efts, Deftru&ire of. .27 



rence. It is faid to be then extremely deftructive, eating through the roots of the 

 ftrongefl ftems of corn plants in a very quick manner. And it is dated, that on 

 taking one of them, and putting it into earth, confiding of a foft black loam, 

 about mid-day, covering it well, at the root of a plant of oats that had fent out 

 thirty-feven off-fets, and which had been well earthed up, the plant on being 

 examined about the fame time the fuccceding day, was found to have its leaves 

 hanging down in a declining ftate, and the root, with the whole of the off-fers, 

 fo injured as to be utterly incapable of recovery. 



In mild feafons, that are favourable for the propagation of grubs, they become 

 numerous and highly detrimental ; but, as has been juft obferved, they moftly 

 perifh annually, the race being preferved only by the depofition of ova in the 

 borders of ditches, plantations, and coarfe fogged herbage, in which the aurelia 

 h protected from injury by moiflure. 



It has been found that the grub commits its principal injury on corn crops 

 juft: after the germination or fprouting of the grain, by devouring or eating away 

 the young (hoot before it mews itfelf above the ground. When the plants are 

 up above the furface, and have acquired conliderable fubftance, there is much 

 lefs danger from the ravages of thefe animals, except where they are very nu 

 merous. During the day they are faid to be moftly found from half an inch to 

 an inch and a half below the furfacej and they are not fuppofed to come much 

 above the ground during the night.* 



Various means have been fuggefted for the purpofe of deflroying thefe ani 

 mals, and preventing their ravages on grain crops, but hitherto probably with 

 out much fuccels. The fubftances that have been chiefly employed in this in 

 tention are lime and faline mattersf ; but it is probable that neither of them arc 

 fully effectual in preventing the deftructive ravages that are often experienced 

 from fuch animals, as it has been found by experiment that the mixing of fuch 

 materials, efpecially the lime with earth, by which it is foon faturated, does not 

 prevent them from propagating and continuing in the mould4 and confequently 

 has but little effect in preferving crops from their attacks. But though lime, 

 when combined with the mould of foils, foas to become perfectly effete by the ab- 

 forption of carbonic acid both from it and the atmofphere, may not have much 



* Annals of Agriculture, vol XXV. p. 407. 



I Of the latter kind are soapers ashes, bleachers ashes, refuse pot-ash, &c.~&c. 

 J Annals of Agriculture, vol. XXV. p. 406. ; Darwin s Phytologia, p. 3G2. ; and Farmer s Ma 

 gamine, vol. II. p. 3()5, 



E 2 



