Cultivation of Arable Land. Wheat Blight in-, g i 



the under remaining perfectly full. In others again, the ears are found to h:-.ve 

 alternately a plump well-filled pickle and an empty hufk ; and that in fome,. 

 though not quite empty, they include only Ihrivelled imperfect grains, or what 

 are termed hungry pickles by dealers. In different inftanccs ears are obferved, 

 that are partly hungry and partly filled in a proper manner; and in a large 

 proportion^ therein an hungry and well- filled grain alternately; in fhort, that 

 various ears, that appear well-filled, on opening the hufks are difcovered to be 

 covered with fpots of a black and rufty caft. A number of the ftems are in fome 

 inftances met with that are perfectly withered their whole length. When ripen 

 ed, the crop, in particular cafes, is obferved to have a dirty fpotted appearance, 

 as if fprinkled with foot, rather than the ufual clean healthy yellow afpect ; and 

 the parts of the draw, or ears, that are not thus fpotted, are neither white nor yel 

 low, as is ufual, but of a colour of the dufky or am kind.* 



Thefe appearances, which mew themfelves in the different ftages of the 

 blight, are fuppofed by the fame author, to prove the exigence of an infect as 

 the caufe of this vegetable difeafe ;j- and that as the greateft injury is almoftia 



* Somcrville in Communications to the Board of Agriculture, vol. II. p. 207. 



f In the paper juft mentioned, which contains much valuable obfervation refpecting the nature of 

 the blight, an infeft that produced much injury to the. ears of the grain is thus defcribed. It 

 bears, fays the writer, a ftriking refemblance to a louse, and when it is firft diftinguifhable by the eye, 

 is of a red colour, nearly refembling that of a boiled lobfter, and fo foft and tender as to be killed by 

 the flighteft preffure ; as it increafes in fue, the colour gradually changes from red to a dirty black r 

 when it becomes ftationary, and continues fo till it dies. During its growth, it alfo lofes this foft 

 tender texture, and in its black ftate feels hard, and as if it were covered with a cruft or fhfill upon 

 the back. It does not appear that this is a new infect, for moft of the farmers with whom the 

 writer has converfed feem well acquainted with it, and all of them, afiert, that, if they are care 

 fully looked for, fome of them may be met with even in the beft fields of wheat every year. It ap 

 pears, however, that they are infinitely more numerous and deftructive in late wet feafons, than in 

 fitch as are earlier and more favourable. In the year 1782, for inftance, when, the crop was uncom 

 monly late, and the feafon very wet and cold throughout, the wheat crop, he fays, almoft entirely 

 failed from the depredations of this infect; and every other inftance that can be recollected of 

 their mifchievous effects, has always taken place in thelateftand coldeft feafons. The obfervations 

 which he made a few fummers ago confirm him in that belief : for he uniformly found that, in propor 

 tion as a field of wheat was early, the injury done was not only muck lefs, but the number of vermin 

 fmaller; while, on the contrary, as the crop was later the mifchief was- in: the fame proportion greater, 

 and continued fo throughout the feafon. The inference he draws from thence is, that wet feafons 

 are more favourable to the generation of thefe infects than dry ones, and that though they are bred 

 in confiderable numbers even in the beft years, yet they come into exiftenceat a period of the feafon 

 \vhenthecropistoofaradvancedto be injured by them. This laft idea was confiderably flrength- 

 aed by trials which he lately made, of placing the iiifefts upon healthy plants at different pe~ 



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