186 



EXPERIMENTS UPON GEASS LAND 



2-51- 



Plot 3 4.-1 



Fig. 39.— Percentage of Oentaurea nigra in the Herbage of the Grass Plots. 

 First Crop, Season 1903. 



Unmanured. Minerals only. 



4-1. Superphosphate. 

 I 8. No Potash. 

 7. Complete. 



Nitrogen only. Nitrogen and Minerals. 



5. Amm.-saits. 4-2. No Potash ^ . 

 17. Nitrate Soda. 9. Complete p™™"" 

 11. Excess N. J '^"'• 

 14. Complete ; Nit. Soda. 



