784 Summary of Agricultural Experiments, [jan. 



culture for the three consecutive seasons 1904-6 at fifty-one centres. The 

 fertilising ingredient that has produced the largest weight of crop has 

 been nitrogen. This has given equally good results, either in the form 

 of nitrate of soda or sulphate of ammonia, and the best results from a 

 mixture of the two. 



The plots receiving the largest amount of nitrogen have given the 

 heaviest crops, and valuing their produce at the same rate as that grown 

 on the other plots, they have given the best financial return. Generally, 

 however, it does not seem advisable to apply more than 2 cwt. of nitrate 

 of soda. 



Phosphates and potash applied alone, and also in combination with 

 nitrogen, have been remunerative. Their effect in preventing exhaustion 

 of the soil, and in improving the quality of the hay, warrants their inclu- 

 sion in any artificial dressing for this crop. The mixture which is 

 recommended as most likely to give general satisfaction is £ cwt. of 

 nitrate of soda, f cwt. sulphate of ammonia (both 95 per cent, purity), 

 2\ cwt. superphosphate (30 per cent, soluble), and | cwt. sulphate of 

 potash (55 per cent, purity). 



Manuring Grass Land (Univ. Coll. of North Wales, Bangor, Agric. 

 Dept., Bull. IX., 1906). — An experiment to test the effect of manures on 

 grass land was commenced in 1902, and various combinations were 

 applied annually in 1903-5, but no manure was given in 1906. The 

 weight of hay is given for the four years. The manures did not produce 

 any large increase in the yield, though they undoubtedly effected 

 considerable improvement in the herbage. 



Another experiment, begun in 1904, was intended to compare the 

 action of the manure sold as basic superphosphate with that of super- 

 phosphate and basic slag. Basic superphosphate is prepared from super- 

 phosphate by adding sufficient lime to give the whole an alkaline 

 reaction. The phosphate obtained is not soluble in the same sense as 

 superphosphate, but is in such a condition that it can be readily taken 

 up by plants, if it is evenly distributed through the soil. The manu- 

 facturers urge that it will prove superior to superphosphate on land 

 deficient in lime, and that where the soil contains considerable quantities 

 of vegetable matter, or is affected with finger-and-toe, it is also to be 

 preferred. 



The result of the three years' trial showed that basic superphosphate 

 is very similar in its action to superphosphate, and in this case, at any 

 rate, decidedly inferior to basic slag. In previous years the action of 

 basic superphosphate has been compared with that of basic slag and 

 superphosphate as a manure for swedes, and Professor Winter remarks, 

 " So far as we have been able to judge, its action is very similar to that 

 of superphosphate, which can be purchased at a much lower price." 



Manuring of Pasture with Basic Slag (Essex Education Com., Field 

 Expts., 1906).— This experiment was intended to test the effect of a 

 second application of basic slag. It is pointed out that when the use 

 of basic slag has resulted in an increase of the leguminous herbage, and 

 this herbage has flourished for a few years, the enrichment of the soil 

 consequent upon the fixation of atmospheric nitrogen by the leguminous 

 plants gives rise to a change in the herbage, and finer grasses begin to 

 replace some of the leguminous plants. It might be assumed from this 

 that a second application of slag at this stage would be unlikely to have 

 a great effect. Two plots which received slag in 190 1, however, were 



