Mays, 1920.] Agricultural Gazette of N.S.W. 321' 



profitable increase in crop yields. The fertiliser merchant cannot be blamed 

 for the poor yields obtained when fertilisers are discontinued, any more than 

 Providence can be censured for semiing good seasons which help to produce 

 good crops and incidentally to make the land poorer. 



Theie is the further complaint that superphosphate has the effect of 

 "hardening" the soil, making it run together after rain and bake quickly,, 

 and thus accentuating the reduction in crop yield. This condition is 

 explained by the same cause — that is, the more rapid exhaustion by the- 

 heavier crops of the soil's organic matter (of which nitrogen is a part), 

 whereas poorer crops grown without fertiliser deplete this organic matter 

 more gradually. In any case, the greater the moistm-e-holding power of 

 the soil the more the fertiliser is likely to be made use of. The intelligent 

 farmer will see to it that the soil retains its moisture-holding capacity by 

 t-nriching it with organic matter from animal and green manures and crop 

 residues. The land is thus kept in good tilth and full use is made of the 

 fertiliser. 



Strange as it may seem, the writer has met landlords who, on the above- 

 fallacious grounds, have absolutely forbidden their tenant farmers to use 

 commercial fertilisers. Tenant farmers on short leases are in some cases 

 loth to use fertilisers because they get no compensation for their residuall 

 values. Such fai'mers have no excuse for this attitude, even on the shortest 

 lease, when they can be assured that the application of fertiliser results in 

 a profitable increase in crop yields. 



Effect of Fertilisers on Maturity of Maize Crops. 



The use of phosphatie fertilisers (particularl}' superphosphate) as an aid- 

 to the early maturing of the crop is a factor which has not previously been 

 given the importance it deserves ; in the Tableland districts the application 

 of I to 1 cwt. superphosphate alone at planting has been observed to hasten 

 the maturity of the maize crop by as much as ten days or a fortnight. 

 In view of the fact that it is never known when extra early autumn frosts 

 will occur, this is a big consideration. The damage done by these unseason- 

 ably early frosts depends on the amount of moisture in the grain at the 

 time it is caught; not only do they reduce the yield because the grain does 

 not fill, but the feeding value of the griiin is also les-eiied. The action of 

 phosphates is to hasten the formation and filling of the grain; and the use 

 of superphosphate in cold climates at planting (which has the direct efifect also 

 of increasing the root development of the young seedlings, tnus giving 

 them a quick start) will do much to lessen the risk of damage which may be 

 caused by early frost. 



Bonedust does not ajjpear to have this power of inducing early maturity 

 in the same degree as superphosphate, and even a mixture of bonedust and 

 superphosphate does not give as marked results in this direction as super- 

 phosphate alone. Nitrogenous fertilisers, like nitrate of soda and sulphate 

 of ammonia, have, on the other hand, the effect of delaying maturity ; and it 

 is probably due to the small amount of nitrogen in bonedu>t that sometimes- 



