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A Common Weed— -The Poppy. 



[APRIL, 



a few convulsive movements, death supervenes owing to 

 arrested respiration. 



The red colouring matter in the petals of poppies is utilised 

 for certain purposes in the arts. 



Prevention and Remedy .—It should be remarked at the 

 outset that great care should be taken to employ only clean 

 seed corn for seed purposes. 



There are several methods by which poppies may be com- 

 bated, and perhaps the most obvious is to prevent the seeding 

 of any plants which may be observed. 



Where seeding is known to have occurred, however, the 

 procedure should be to encourage early germination in spring 

 by endeavouring to keep the seeds at the surface and procure 

 a fine tilth. In damp weather the seeds will commence 

 growth, and as soon as fine, dry weather occurs, surface culti- 

 vation with the hoe, light harrows, the poppy killer (see 

 Journal, July, 1904, p. 196), and the various types of 

 American weeder, will tend to destroy the young plants. A 

 repetition of this procedure will account for a considerable 

 proportion of the growing poppies, and after the corn crop 

 is too high hand weeding may need to be resorted to. 



Where the poppies occur in overwhelming numbers it may 

 be advisable to forego a corn crop and take an extra root crop 

 in the rotation, and by this means the poppies may be largely 

 reduced. 



In experiments conducted at the Woburn Experimental 

 Farm in 1900 and 1901, poppy plants (P. Rhoeas) were injured 

 by spraying with a 2 per cent, solution of copper sulphate 

 just before they came into flower, but afterwards recovered. 

 When the solution was applied to the underside of the leaves 

 as well as to the upper surface, "the leaves turned brown, 

 became shrivelled, and to a great extent the plant was killed, 

 for the seeding was almost entirely prevented, the flower 

 heads withering up." Now in a tall corn crop with poppies 

 nearly at the flowering stage, spraying could only be done 

 by hand, and the wetting of the underside of the leaves could 

 scarcely be accomplished. But since it is well known that 

 in charlock spraying a 3 per cent, solution of copper sulphate 

 does little if any damage to the corn crop, a 3 per cent, solu- 

 tion might be tested on poppies when they are no more than 



