134 MASS. EXPERIMENT STATION BULLETIN 212. 



Table 4. — The Destructive Treatments. 



Since the farming system followed was one which logically and on many 

 soils inevitably results in need of complete fertilizer applied in large quan- 

 tities, it is not astonishing that the one-sided treatments should give such 

 poor results. 



It will be noted that the above-mentioned destructive treatments are 

 those which contain no potash, which fact is of importance in connection 

 with the lime history of the field. Commencing in 1899, lime was appUed 

 at frequent intervals, and in generous quantity. It has sometimes been 

 claimed that such use of lime makes soil potash available. Did it have 

 such an effect, it would be expected that the yields on the nitrate of soda, 

 the dissolved boneblack (acid phosphate) and the nitrate and boneblack 

 plots would approximate those secured on equivalent treatments with 

 potash added. This expectation has not been realized. There is no in- 

 dication in the data at hand that lime has had any measurable or signifi- 

 cant effect in increasing the availability of soil potash. 



Manure versus Fertilizer. — Table 5 shows the comparative corn yields 

 year by year, mth averages for the two periods in question, of Plot 7, re- 

 ceiving manure, and Plot 14, receiving complete fertilizer. 



Table 5. — Comparison of Manure and Complete Fertilizer. 



