11 



CARROT. 



" Rust." Carrot Fly. PsUa roscp, Fab. 



PSILA KUS/E. 



1, 2, and 3, maggots of Carrot Fly, nat. size and mag. ; 4, infested Carrot; 5 and 6, 

 pupffi, and 7 and 8, Carrot Fly, nat. size and magnified. 



Carrot attack, commonly known as rust, is a constantly recurring 

 cause of loss, and probably will continue to be so as long as the 

 requisite treatment is put oE until the presence of the grub at the roots 

 is shown by the discoloured and dying leaves, instead of measiu'es 

 being taken previously, at the right time, to prevent the Eust Fly going 

 down into the ground by the Carrots to lay her eggs, and thus start the 

 infestation. A large proportion of the minute directions given by 

 successful Carrot growers as to composts, preparation of ground, &c., 

 turn on this point, that is, having the land in such a state that it will 

 not draw away into cracks and so lay the roots open to attack ; but 

 besides this, the great point of all in forestalling attack, and one with- 

 out attention to which all other measures may fail, is such treatment 

 at thinning time as may deter attack, or may so close the disturbed 

 and shaken open ground that the Carrot Flies cannot get down to 

 the roots. 



These facts have long been known, and the best methods of culti- 

 vation adopted for meeting the difficulty, contributed mainly by Scottish 

 superintendent gardeners, have already been given in these Keports ; 

 but during the past year so much advance has been made, both in 

 variety of insecticides and methods of applying them, that I give a few 

 suggestions once again as to treatment at thinning time. 



The method of life of the Carrot Fly is to go down into the ground, 

 where she can find a chink or cranny, by the Carrots. There she lays 

 her eggs on or by the roots, and the little yellowish or whitish maggots 

 which hatch fi-om these work their way into the root itself, or, if this is 

 still very small, often destroy the lowest part. When full fed they 

 leave the Carrots, and turn to the chrysalis state in the ground. The 



