FIELD CROPS. 



31 



The complete fertilizers contained only TO per cent of the constituents applied 

 singly and are therefore not deemed comparable with them. 



Fertilizer experiment 2 was a continuation of pot fertilizer experiment 2 

 of the 1907 series. The pots laid fallow 6 months, then the originally fertilized 

 soil was submerged, stirred to a depth of 4 in., allowed to settle, and planted 

 with five 15-day-old seedlings per pot of Japan rice No. 153. Three pots con- 

 stituted "each series, one limed, one drained, and one untreated, save for the 

 application of the fertilizer noted. The limed pots showed a depression of 14 

 to 40 per cent in yield of straw and paddy. Draining and consequent leaching 

 produced no apparent decline. A comparison of the results of the 2 years shows 

 that the more vigorous varieties derived the greatest benefit from the fertilizers 

 applied. A residual value appears from most fertilizers when applied before 

 the i)lanting of the previous crop, but this residual value increases with the 

 application of fertilizer to the previous crop when well advanced in growth. 

 It remains to be determined whether the greater residual benefit of the later, 

 application of fertilizer outweighs the greater immediate benefit of application 

 before planting. 



Fertilizer experiment 3 consisted of 3 tests, at different seasons of the year, 

 of the relative value of the different sources of nitrogen. The fertilizers applied 

 and results are summarized in tlie following table: 



Relative value of various forms of nitrogen for rice. 



Plat 

 num- 

 ber. 



Fertilizer applied. 



Amount 

 of ferti- 

 lizer per 

 acre. 



Height 

 of plants 

 at 

 matu- 

 rity. 



Green 

 weight, 

 whole 

 plants. 



Number Weight 

 of culms I of paddy 



per 

 clump of 

 6 plants. 



per 100 

 clumps 

 of rice. 



Date 

 of ma- 

 turity. 



Check (no fertilizer) . . 

 Complete fertilizer . . . 



Stable manure 



Complete fertilizer 



Check 



Green manure 



Sulphate of ammonia , 



Lime nitrogen 



Check 



Nitrate of soda 



Pounds. 



350 



5,000 



350 



20, 000 

 200 

 266 



Jnch€!>. 

 33-35 

 38-40 

 40-45 

 40-43 

 34-35 

 40-48 

 44-48 

 38-42 

 30-34 

 35-38 



Pounds. 

 45 



48 

 55 

 51 

 46 

 60 

 64 

 50 

 44 

 47 



15-20 

 20-22 

 21-23 

 20-25 

 17-20 

 20-26 

 25-27 

 22-24 

 16-18 

 20-22 



Pounds. 

 5.3 

 7.1 

 6.8 

 7.9 

 5.7 

 5.9 

 8.1 

 6.7 

 5.2 

 5.9 



July 20 

 July 22 

 July 25 

 July 20 

 July 22 

 July 30 

 July 25 

 July 25 

 Julv 20 

 July 28 



Fertilizer was applied to plat 4 before planting. All other fertilizers except 

 stable manure and green manure were applied when the crop was two-thirds 

 grown. The green manure consisted of legumes and weeds. 



Fertilizer experiments 4 and 5 to show the relative value of commercial forms 

 of nitrogen as fertilizers for Japan Seed and Hawaiian Gold Seed rice agreed 

 with former experiments for the same purpose in showing the greatest benefits 

 from sulphate of ammonia, lime nitrogen, and nitrate of soda, in the order 

 named. In experiment 4, the Gold Seed required 30 days longer than the Japan 

 Seed to reach maturity, as an apparent result of fertilization. Nitrate of soda 

 appeared to give its maximum benefit from late application, whereas sulphate 

 of ammonia must be applied earlier and lime nitrogen still earlier to produce 

 their maximum results. Large applications of nitrate of soda wasted most of 

 the nitrogen. 



Fertilizer tests on dry-land rice showed a less definite influence on the yield 

 of paddy, on account of the very dry season. On both silt and gravelly loam 

 muriate of potash, sulphate of ammonia, and nitrate of soda increased the yield 

 of straw in degrees varying in the order named. No apparent influence was 

 exerted by the other constituents applied as in experiment 1. 



