I - I I ■ I \ ■ V 1 1 I 



r. r, r r f •/ n ri I f 



TRANSACTIONS 



OF THE 



HERTFORDSHIRE NATURAL HISTORY 

 'iOps^ SOCIETY. 



ON METHODS OF PREVEXTION OF INSECT-INJURY. 



By Eleais^oe A. Okmekod, F.M.S. 



Read at Watford, 22nd November, 1881. 



AiroifGST the various metliods by which the attacks of injurious 

 insects to our crops may be prevented or remedied, none are so sure 

 as those that are based on natural principles, together with broad 

 measures of cultivation, that is to say, on taking advantage of such 

 peculiarities in the habits of the so-called pests as may afford points 

 at which they are open to attack ; and secondly, though in a lesser 

 degree, we may utilize peculiarities in their nature which are 

 affected by meteorological influence, or, in other words, by the 

 weather. It is frequently remarked that "we cannot alter the 

 weather," — but this is not quite the case, for drainage and irriga- 

 tion on a large scale have effect on atmospheric conditions, and 

 may be brought also to bear as means of prevention of attack of 

 serviceable practical use to the field crops, much more than they 

 are at present. We also find that by observing the way in which 

 continued sunshine and drought, or on the other hand long wet 

 weather, or sudden and violent rainfall in a dry season, affect 

 various kinds of insects most destructive to our crops, we may 

 follow the lesson up practically by artificial means to our own 

 great advantage. 



Similarly amongst owx forest or orchard trees, although we can- 

 not have sunshine at command, we may often expose a much larger 

 surface to its influence, and thus act at once on a broad scale on 

 some of the injurious insects with much more effect and less cost 

 than by any local applications, such as dressings, washings, or 

 other remedies. 



VOL. II.— PAHT I. 1 



