4 2 



COMMON WEEDS 



ments that mineral manures tend to reduce weeds to a 

 minimum ; nitrogenous manures favoured the growth of 

 weeds, which attained their most vigorous growth on 

 undunged land. His results may be given thus: 1 



Undunged 



Sulphate of Ammonia 

 Nitrate of Soda 

 Sulphate of Magnesia 

 Common Salt . 

 Sulphate of Potash 

 Carbonate of Lime 

 Quicklime 

 Superphosphate 

 Gypsum . 



Percentage of Weeds 

 contained in the Crop. 



30.0 



26.0 



i o.o 



7.0 



5-5 



4-9 



4-5 



4-4 



1-9 



Collection of Weeds by School Children. Dr. Ewart, 

 Government Botanist, Victoria, called attention last 

 year 2 to a plan for suppressing weeds which is worthy 

 of consideration. It consists in offering prizes to school 

 children for collecting certain weeds, and Dr. Ewart 

 mentions an instance in which, after prizes were offered 

 by the police magistrate at some (then recent) prose- 

 cutions under the Thistle Act, 12,000 plants of Ragwort 

 were brought in during the first four days, and this 

 number quickly rose to nearly 20,000 plants. 



In both preventive and remedial treatment, however, 

 each case must be taken on its merits, and after con- 

 sideration of the individual conditions concerned ; at 

 the same time it must be emphasised that if good results 

 are to be obtained, perseverance and faithful attention 

 to the principles involved (not forgetting the life history 

 of the plant) are essential. 



1 Dr. Fr. Nobbe, Handbuch der Samenkunde, 1876, p. 578. 



2 Jour. Dept. Agric., Victoria, August 10, 1908. 



