592 Summary of Agricultural Experiments, [qcty, 



manure for " Upper Hale " and superphosphate for " Five and Three 

 Acres." Analysis indicated that both soils contained a sufficient quantity 

 of natural potash, but nevertheless portions of the experimental area 

 were marked out for treatment with potash salts. The analytical indica- 

 tions were borne out by the fact that while phosphates have produced 

 a large increase of hay, potash salts have thus far had but a small effect 

 on either of these fields, although in other trials potash salts have proved 

 very valuable in improving both the yield and the composition of the 

 hay. 



The results of the first eight years' experiments are summarised 

 below. The natural yield of the land may be seen from the quantity 

 of hay yielded by a portion of each field which has been left continuously 

 unmanured. The yield of the unmanured land is tending to increase 

 slightly but steadily year by year, by reason of the fact that, after hay 

 harvest, the whole of the plots are thrown open to autumn grazing with 

 the rest of the field. Under these conditions the unmanured plots share 

 to some extent the indirect manurial advantage of the consumption by 

 grazing stock of trie richer herbage of the manured land. This gradual 

 improvement appears in both fields. 



No exact botanical survey has yet been made of the plots, but, 

 speaking in general terms, it may be stated that the unmanured land 

 is conspicuous for the poor, wiry nature of its grass and the abundance 

 of plants which, in a pasture, may be regarded as weeds. On all the 

 manured plots, on the other hand, there is an abundant growth of rich 

 grass. Where phosphates, or phosphates and potash salts, have been 

 continuously applied without nitrogen, the growth of plants of the 

 clover kind is most conspicuous ; while on the plots on which nitrate of 

 soda has been continuously used without phosphates or potash (a mode 

 of manuring which on general principles is not to be recommended), 

 the grasses, as distinguished from clovers, are most prominent. The 

 best herbage, however, in which clovers and grasses appear to flourish 

 with equal vigour and luxuriance, is found on the plots on which both 

 phosphates and nitrate are used every year. 



Five and Three Acres. 



Annual Yield of Hay per Acre. 



Average gain 

 Eight years' due to 

 1908. 1909. Average. Manuring. 



Manuring per Acre. Tons. Cwt. Tons. Cwt. Tons Cwt. Tons. Cwt. 



No Manure 



Superphosphate (3 cwt.) 

 Superphosphate as above, with 



Sulphate of Potash * 



Superphosphate as above, with 



Nitrate of Soda (2 cwt. in 1902, 



I 9°3? I 9°4» an d 1905 ; cwt. 



in 1906, 1907, 1908 and 1909) 

 Superphosphate and Nitrate of 



Soda as above, with Sulphate 



of Potash *< 



Nitrate of Soda without Phos- 

 phates or Potash 



0 



IQl 



0 



14 



0 







I 





1 



i5i 



1 



"I 



I I j 



I 







16 



1 



I2| 



I 2 





14 



2 



3.1 



2 



I 



1 10^ 



I 



14 





4 



2 



2 



1 m 



I 



7 



1 



9 



1 



I2| 



1 2 



