} May, 1900. | QUEENSLAND AGRICULTURAL JOURNAL. 403 
Selence, 
SOME QUEENSLAND SOLLS. 
a By J. GC. BRUNNICH, F.C.S., 
Chemist to the Department of Agriculture. 
|#or the information of the managers of the various State farms complete 
| ®alyses of their most important soils were carried out at the Laboratory of the 
| “epartment of Agriculture; and, as these soils come from various districts in 
| Queensland, they will be found of general interest, and are given now in tabu- 
ted form. 
The soils were all prepared and analysed in exactly the same manner, to 
| dbtain strictly comparable results ; and in all cases mechanical analysis and so- 
| Wed agricultural analysis (extracting the soil with boiling hydrochloric acid of 
| “ttain strength) were carried out. 
In order to enable some of our farmers to interpret these analyses, I will 
_ | 20w give a short explanation of the various figures given. 
|. Once for all, it must be understood that the agricultural analysis does not 
| ve the total amounts of plant foods present in the soils; only a so-called 
| tbsolute analysis will give the actual amount of every chemical compound. For 
stance, the portion of soil (No. 7) which amounted to 63469 per cent., and 
Which was insoluble in boiling hydrochloric acid was by further treatment— 
| Ustly, with strong sulphuric acid; and secondly, with hydrofluoric acid—made 
| “luble, and found to contain considerable amounts of the plant foods— 
| ime and potash—which, however, are in such an insoluble form that they are 
| 70t directly available for the plants. Hven the whole of the amounts of 
thosphorie acid, lime, and potash, given by the extraction of hydrochloric acid, 
| ®e not by any means in a readily assimilable form, and for this reason—by 
any authorities, the value of agricultural analysis of soils is completely denied, 
‘nd methods are tried to be found which should give the éxact amounts of 
| “neral matter made soluble by the action of roots on the soil. ‘The solutions 
' various weak acids have been used for this purpose; and Dr. Maxwell has 
| “scovered a method suitable for the volcanic soils of the Hawaiian Islands. He 
| "kes a 1-per-cent. solution of aspartic acid, and finds that by acting twenty-four 
Ours on Hawaiian soils the same amounts of lime, potash, and phosphoric acid 
‘te removed as by the production of ten crops of cane (‘‘ Lavas and Soils of 
© Hawaiian Islands,” by Dr. Maxwell; page 181). It seems, however, that 
this method is not applicable to every kind of soil, and, I presume, not for every 
| “nd of crop; but new methods haye to be worked out for the varying conditions, 
| Yhich involve an enormous amount of most careful investigations. or this 
Taxon, we have to be satisfied with the agricultural analysis, and, if carried 
Sut exactly alike and in connection with mechanical analysis, their 
‘alue for the farmer cannot be denied, as it is quite evident that, if the 
nalysis shows a great deficiency in either nitrogen, potash, lime, or phosphoric 
‘aid, they must be applied by artificial manuring. But here, again, rule of 
thimb is not sufficient, and because, for instance, nitrogen is wanted, it would 
} 20t do in all cases to green manure the ground, or to apply nitrogen in the form 
| sulphate of ammonia, or again in the form of nitrate of soda. The nitrogen 
| ‘generally given in either of these three forms, but which one to use depends 
_ | ‘Mtirely on the nature of the soil, on the climate, and on the crop to be grown. 
| “cavy soils inclined to be wet might be completely ruined for a time by heavy 
een manuring, as the ploughing under of a lot of green stuff inclines to sour 
he soil ; and this is only remedied by a heavy dressing of quicklime. or this 
| *ason, it is very important that the samples of the soil should be taken by 
a | ptbetent persons—if possible, by the analyst himself—and all particulars about 
| the peculiarities of the land itself, climate, crops, &c., be carefully noted and 
Ported. 
fein tenia 
hh 
