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to the crops sown alone or with clover or seeds. In the 

 fields above mentioned the worst attacked were barley 

 alone ; the least attacked had clover and seeds. 



Eotation of crop which excludes wheat, barley, or rye 

 on attacked land, is exceedingly important ; the Hessian 

 Ply only attacks some of the cereals, therefore all 

 leguminous and root-crops are perfectly safe, and like- 

 wise, as they cannot be used as food, help greatly in 

 lessening the prevalence of the pest. 



The choice of kinds of corn with hard stems, such as 

 cannot be easily injured by the suction of the maggot, 

 is also particularly dwelt on and kinds named, but as 

 these differ from our English kinds it is unnecessary to 

 give the list. A summary of the above might be shortly 

 stated thus, beginning at harvest-time* : 



If possible reap so as to leave the "flax-seeds " in the 

 stubble, and destroy this infested stubble; otherwise 

 treat the harvested straw so as to destroy them. 



If flies are likely to be about let the self-sown corn 

 on fields that were infested sprout, and presently turn 

 sheep on to feed off the infested plants, and then plough 

 the remains in. Ploughing in infested stubble is also 

 useful. " Bait " may also be had recourse to by sowing 

 strips or patches of corn to attract the fly, and treating 

 them as above. 



Late sowing, so that the young wheat will not be up 

 until the autumn brood is dead, is a most important pre- 

 caution, but, as it appears to be safe if put in after the 

 beginning of October, this point is usually met in this 

 country without special arrangements. 



Dressings, and mechanical measures, as rolling, &c., 

 may or may not answer, according to circumstances. 



* In American treatment the great importance of preserving the insect 

 parasites, which feed on the Hessian Fly in its early stages, is most 

 urgently insisted on, as in that country they are as much looked to for 

 keeping down the attack as Ladybirds are in our own as a check on Hop 

 Aphis. Consequently burning stubbles, or burying them deeply, or other 

 treatment which would kill parasites as well as pests, is thought doubt- 

 fully of. In the foregoing notes I have not entered on this consideration, 

 because as yet we do not know that the parasite insects have followed in 

 the train of the fly. 



