4 66 



Destruction of Charlock. 



to exist in early summer, when the cultivated crops on which 

 it preys are, for the most part, absent from our fields, did it 

 not find weeds like charlock to supply it with food. Then, 

 again, the microscopic fungus that causes finger-and-toe 

 finds a congenial habitat in the roots of this plant, which 

 may thus do much to carry the disease over the years that 

 separate two turnip crops. 



In the case of root crops reasonable attention in the matter 

 of horse and hand hoeing may usually be depended on to 

 keep charlock in check. It is when present in spring corn 

 crops that it is most troublesome. Various expedients have 

 b6en tried with the view of curtailing the development of the 

 weed. If the field be harrowed, and the sowing of the grain 

 be somewhat delayed, a large proportion of the charlock 

 s eed will be induced to germinate, and the resulting plants 

 may be afterwards destroyed by harrowing. Hand and horse 

 hoeing may be practised — providing the corn has been drilled, 

 and has not been sown down with grass or clover seeds. At 

 a later stage of growth the flower heads may be more or less 

 effectively knocked off by means of a special machine, the 

 use of which diminishes the formation of seed, but does little 

 to mitigate injury to the corn crop immediately concerned. 



In 1897 attention was called to the possibility of getting rid 

 of charlock in corn crops by means of the application of cer- 

 tain solutions which, it was contended, could destroy the weed 

 without injuring the cereal. During the past two seasons this 

 method of dealing with the pest has been extensively tested in 

 Great Britain, and, as a whole, the results have been success- 

 ful. The substances chiefly tried have been copper sulphate 

 and iron sulphate, and good results have been got with both. 

 Although the former at present costs about 30s. per cwt, as. 

 against 4s. to 5s. in the case of the latter, the solution of iron 

 sulphate must be used so much stronger than the other that 

 the difference in the cost of material is less per acre than 

 would at first sight appear. Moreover, copper sulphate 

 deteriorates less by keeping, is more easily manipulated, and 

 does less injury to the clothes of the workmen. 



Experience indicates that good results will, as a rule, be 

 got by dressing an acre with, at most, 40 gallons of a 4 per 



