1 8 



Eradication of Charlock. 



the Technical Instruction Committee, under the direction of 

 Mr. Campbell. 



The experiments hitherto made in this country have 

 demonstrated clea ly that sulphate of copper and sulphate of 

 iron solutions both kill charlock if made of a certain strength 

 and, at the same time, do not injure the corn plants among 

 which it is growing if they are properly made and carefully 

 applied. In a circular dated November, 1898, Dr, Somerville 

 says : — " There is no doubt that when this new method of 

 destroying charlock is better known, farmers who have 

 infested ground to deal with will obtain spraying machines, 

 or men will be found to take up the work as a commercial 

 venture." 



Experiments were made by the Essex Technical Education 

 Committee upon barley about the middle of April, 1898. 

 Several strips of a field of barley were sprayed with one^ 

 two, four, and six per cent, solutions of sulphate of copper, 

 in quantities varying from 10 to 100 gallons per acre. A one 

 per cent, solution was found too weak to kill all the charlock ; 

 a six per cent, solution on the other hand proved too strong, 

 and damaged the barley. With regard to trie quantity to be 

 applied, at the rate of 10 gallons per acre some charlock 

 escaped the spraying, and 100 gallons was found to be far 

 too much. The general outcome ol the experiments showed 

 that a two per cent solution applied at the rate of 25 to 50 

 gallons per acre, during dry weather, and at an early period 

 of growth, was completely successful without injuring the 

 barley. In June the sprayed strips of barley were entirely 

 free from charlock, while adjoining strips unsprayed were 

 yellow with its flowers. 



In 1898 similar experiments were conducted under the 

 auspices of the Lancashire Technical Education Committee 

 with sulphate of iron, applied to oats in solutions of 13 to 20 

 per cent. In the beginning of July one plot of oats was 

 sprayed witn a 15 and another with a 20 per cent, solution 

 of sulphat e of iron, with the result that in both plots the 

 charlock was quite exterminated and the few thistles were 

 blackened, but the oats and young seeds showed no injurious 

 effects. In the unsprayed plots the charlock had grown 



