188 



EXPERIMENTS UPON GRASS LAND 



Fig. 40. — Percentage of Rumex acetosa in the Herbage of the Grass Plots. 

 First Crop, Season 1903. 



Unmanured. Minerals only. Nitrogen only. 



4-1. Superphosphate. 5. Amm. -salts. 



i 8. No Potash. I 17. Nitrate Soda, 

 I 7. Complete. 



Nitrogen and Minerals. 

 4-2. No Potash ^^^^. 

 9. Complete ,- .. 

 11. Excess N. J '*"'• 

 14. Complete ; Nit. Soda. 



