250 EXPERIMENT STATION RECORD. 



the edg-os of the leaves of plumeless thistles (Carduus), Vmt did not 

 appear permanentl}^ to injure the plant. A 5 per cent solution 

 destroyed some whole leaves and checked growth for several days. 

 A 10 per cent solution entirely destroved young* plants. A 1.5 per cent 

 solution applied to plants 20 to 30 cm. in height entirely destro3'ed a 

 part of them. In experiments with white mustard, a 10 per cent 

 solution completely destroyed the plants in those cases in which appli- 

 cation was made before the flower buds were developed. If applied 

 later, it was not effective. 



The author then proceeds to report very briefly on some experi- 

 ments made by himself along this line, using, however, in this case a 

 solution of superphosphate. Details of the experiments are not given, 

 but it is said that ver}^ satisfactory results w^ere reached in experi- 

 ments with various cruciferous plants. The experiments were repeated 

 with mixed solutions of superphosphate and sulphate of ammonia, and 

 in this case a solution of 5 degrees of densit}^ proved ver}^ efficient. 

 The experiments are to be continued. 



Results of experiments on the spraying of charlock, P. H. 

 FouLKES {Jour. Beading Col.^ Enghind^ Sup. 9, pp. oo~o9). — Spra3'ing 

 experiments were conducted in 6 localities, in which copper sulphate 

 in strengths of 2 to 6 per cent and quantities of 25 to 75 gal. per acre 

 was tested. The applications were made under different climatic con- 

 ditions on wheat, barley, and oats at different stages of growth, when 

 the charlock plants were quite young, just before flowering, and while 

 in flower. On the whole, the experiments were considered to establish 

 the value of copper sulphate as a means of destruction of charlock. 

 For the best effect of spraying the author considers the following con- 

 ditions necessary: A clear, still, dr}' day, the application of a 2 per 

 cent solution at the rate of 50 gal. per acre before the charlock comes 

 into flower, and the thorough application of the spray, in which the 

 nozzle should be held low so that the sprav may fall upon and not be 

 driven against the plants. If these conditions are complied with, it is 

 thought that one spraying will ])e sufficient lo destroy the weeds. If 

 rain falls within 21 hours after the spraying, it is advised that the 

 application be repeated. 



Spraying of charlock (Jour. Bd. Agr. {London], 7 {1900), No. 1, 

 pp. J^j-J/)). — A l>rief report is given of experiments conducted in north 

 Wales in regions which are notably infested with this weed, in which 

 one-eighth-acre plats were sprayed with copper sulphate, and compari- 

 sons made with other plats sprayed with iron sui})hate. Iron sulphate 

 failed to produce any appreciable effect upon the weeds, while copper 

 sulphate gave better results although not altogether satisfactory ones. 

 The sprayings were probabh^ made too late in the season, as the results 

 seem to indicate that the advantage of spraying depends largely on 

 the age of the charlock at the time of spraying. No injury to the 



