14 



4 to 5 per cent. ; and in heavy clays, from 8 to 10 per cent. Mr. W. 

 Lehmann, of Murray Bridge (13.90 in.) read a very good paper on 

 "How to Grow Good Crops with Commercial Fertilisers in Dry Dis- 

 tricts (from 12 to 14 in.)" He also recommends early fallow to a 

 depth of 4 to 7 in., and, whereas sandy soils grow the finest crops- 

 of wheat with artificial manures, he maintains that we should pre- 

 pare all soils to closely resemble sandy soils by fallowing about 5 in. 

 deep and subsoiling another 7 in., where such can be done fairly 

 easily, and thus conserve more moisture. Mr. Jos. Correll, of Minla- 

 ton (Y.P.), in his very practical paper read at the Congress of 1898, 

 has come to the same conclusion after he had subsoiled some land, 

 Mr. Lehmann also suggests to give to the subsoil a certain quantity 

 of slow-acting manure, as Thomas phosphate, guano, guano super, or 

 bonedust. To drill in commercial manures to a depth of 2 to 4 in. 

 gives the grain for a time a luxuriant growth, which cannot after- 

 wards be maintained in all cases unless fed from the subsoil. 



Professor Dr. P. Wagner states that generally cereals require 

 manures containing all three plant foods, only that barley and rye 

 require less nitrogen than oats and wheat. As normal doses (for 

 Germany), within which you may select them for cereals, in accord- 

 ance with the state of the soil, he recommends per acre : 



Nitrogen. Phosphoric Acid. Potash. 

 Low manuring ... 12 Ibs. 24 Ibs. 24 Ibs. 



Medium ... 20 Ibs. 40 Ibs. 40 Ibs. 



High 48 Ibs. 64 Ibs. 80 Ibs. 



12 Ib. of nitre-gen are found in about 75 Ib. of nitrate of soda, 

 or in a little less of sulphate of ammonia ; 24 Ib. of phosphoric acid 

 in about 130 Ib. of Thomas phosphate, or in somewhat less super- 

 phosphate ; 24 Ib. of potash in 180 Ib. of kainit, or in about 40 Ib. 

 of muriate or sulphate of potash. 



These will be found large quantities for South Australia, if it 

 comes to high manuring ; but it must not be forgotten that Thomas 

 phosphate, which Wagner had in view, has, as well as all the potash 

 manures, a large residual value. Dr. Aitken concluded from expe- 

 riments made by him from 1887 to 1893 that sulphate of potash had 

 a tangible residual value for five years and muriate of potash for four 

 years. The quantity applied to a cereal crop may, therefore, be- 

 larger than required, but is available for future years. Our clay 

 soils generally do not seem to require any manuring with potash as 

 yet, but it is quite different with sandy soils. 



WHEAT. 



A few words on the tillage of wheat from a lecture by Pro- 

 fessor Maercker may be useful, especially for exposed positions : 

 "For wheat the land should not be too finely pulverised ; it prefers 

 a certain quantity of clods in the soil, which keeps off the wind, 

 which often plays mischief in the spring during long, anxious periods 

 of drought, when the young plants find shelter in the clods/' He 

 also said : "A dressing of nitrate of soda for wheat is absolutely 

 necessary, except after lucerne broken up, or an other leguminous, that 



