612 Journal of Agriculture, Victoria. [10 Oct., 1918. 



experiments wliich are being carried out there, one, knoAvn as tlie Perma- 

 nent Fertilizer Test, has been conducted for the past five years with the 

 definite object of elucidating problems connected with the use of ferti- 

 lizers. The records of grain yielded by the various plots in this field 

 have already been published, and, as time advances, the effect of the 

 different fertilizers is becoming accentuated, and the opportunity for 

 making reliable observations is thereby increased. 



In order to assist in arriving at a correct judgment of these observa- 

 tions and results, the following brief description and history of the land 

 and scheme of working is given : — 



The soil in the field in which the plots are located is a shallow light- 

 red to grey loam, overlaying clay, with basaltic rock coming close to the 

 surface in places. Prior to the establishment of the Research Farm in 

 1912 it was cultivated for many years chiefly for growing hay, and at 

 '.he commencement of these tests was deficient in humus and in an 

 exhausted state. 



The area was pegged out as an experimental field in 1913. The 

 plots are each a quarter of an acre in extent, and (with the exception of 



Fig. 1. — Showing effect of the third application of i cwt. of superphosphate 

 per acre on the third experimental crop compared with the adjoining 

 unmanured plot. 



two which are cropped each year) are set out in duplicate in order that 

 they may be sown on fallow or in rotation with a leguminous crop, one 

 section being in crop and the other in fallow or green crop each year. 



Observations Regarding Residual Effect. 



During the period 1913-18 there have been some striking differences 

 in the growth of the self-sown crop which came up on the various plots 

 in the autumn, and was allowed to grow till fallowing time (August- 

 September). These growths give an indication of the residual effect of 

 the different fertilizers, and, being side by side in the same field, and a 

 complete history of previous treatment being available, there is a good 

 opportunity to obtain reliable information. While the results are 

 interesting and considered worthy of publication for the information of 

 those using, or contemplating the use of, artificial fertilizers, it should 

 be remembered that it is too early to be dogmatic on the different points, 

 and, as time goes by, it may be necessary to revise some of the conclusions 

 now arrived at. 



