432 



KNOWLEDGE. 



November, 1910. 



sulphate, arsenate of soda, and 

 so on. are dealt with. 



The foregoing notes show con- 

 clusively that in one way or 

 another man\' weeds may be 

 attacked by means of solutions 

 of chemical preparations, with 

 good prospects of preventing 



seeding or 



of destroying the 



plants altogether. It is, however, 

 still desirable that exhaustive 

 experiments should be conducted 

 on a co-operative basis in differ- 

 ent parts of Great Britain, 

 for the effects of the various 

 solutions \'ar\- with the plant 

 sprayed, the local meteoro- 

 logical conditions, and the 

 thoroughness with which the 

 work is carried out. \\'ith the 

 results of such experiments 

 placed clearl\- before them. 

 British farmers would have 

 some definite information on 

 A plot of lawn upon the North Dakota AKi'icnltural College campus infested by which to proceed. We hope 

 dandelions untreated before blossoming time. Left continuation of Figure 14. tJ-iqt- fl-|p nrenaration of this 



article w ill not have been in \-ain. 



Figure 13. 



(From Bolley's Bulletin, No. 80, see Knoxclccli>e, No. 507, p. 395.. 



Calcium CNanamidc has also 

 been found useful for destroying 

 charlock in corn crops.* 



The action of petrol on certain 

 plants has been observed at 

 the \\'oburn Experimental Fruit 

 Farm.^ and it was noted that 

 the popp\', teasel and wild 

 strawberr\" were practicalh' 

 killed. 



The efficac}' of carbon bi- 

 sulphide in killing large troi.Mcal 

 " weeds " has lately been dis- 

 cussed b\" E. \'. \\'ilcox in a 

 press bulletin issued from the 

 Hawaii Agricultural Experiment 

 Station, and plants app>ear to be 

 destro\'ed owing to the freezing 

 effect. 



The results of experiments 

 at the \'ermont Agricultural 

 Experiment Station and else- 

 where are summarised in Farm- 

 ers' Bulletin, No. 124 of the 

 U.S. Department of Agriculture 

 — and salt, carbolic acid, liver- 

 of- sulphur, kerosene, cop])er 



IGURE 14 



.■\ plot of lawn upon the North Dakota Agricultural College campus infested by 

 dandelions of the same strength of growth as those shown in Figure 13. but J 

 treated with iron sulphate solution thrown by a traction sprayer two weeks before ^ 

 blossoming time. Compare with Figure 13. (From Bolley's Bulletin, No. 80, see 

 Ktioicledge, No. 507, p. 395). These two photographs show in a striking manner 



the effects of spraying. 



'■■ Jtiiir. Rd. Agrlc, Dec, l')()7, p. 568; Jan.. 1909, p. 776. 



I 10th Annual Report, 1909, p. 20. 



