402 QUEENSLAND AGRICULTURAL JOURNAL. [1 May, 1898. 
14. The high-grade commercial salts used for fertilising purposes are 
manufactured from the crude salts, and are to be preferred when shipments 
are made to great distances and at high rates of freight. 
15. The principal crude potash salts used for fertilising purposes are 
kainite containing 12°5 per cent. of potash, and carnallite containing 9°9 per 
cent. : 
16. Tobacco waste, cotton-seed hulls, and wood ashes also furnish im- 
portant quantities of potash for fertilising purposes. 
17. Recovered marsh or swamp lands and lands containing large quan- 
tities of sand, need, almost universally, potash fertiliser. The percentage of 
potash in soils usually rises with their content of clay. 
18. The maximum effect from fertilisation with potash is secured only when 
.other plant foods are supplied in such a way as to make a well-balanced ration, 
and where proper methods of culture are employed. 
19. Lime is an important adjunct to potash fertilisation, and, as a rule, 
should be added to a soil in large quantities wherever potash is applied. 
20. The best kind of potash fertiliser is determined by local conditions, 
freights, and the nature of the soil and the crop. Fertilisers containing 
considerable quantities of chloride should never be applied to vineyards and 
tobacco fields. i 
21. In intensive pot or garden cultivation, where highly-concentrated plant 
foods are required, and where the cost of the fertiliser is unduly great, 
potash may be applied in the form of potash salts or nitrate. 
22. In some soils potash salts, in common with other saline bodies, pro- 
duce injurious effects by reason of their hygroscopic nature, attracting 
moisture, and, on drying, producing a cementation of the soil, which renders 
it impervious to water and impenetrable by the rootlets of plants. C 
23. Crude potash salts can be applied with benefit in the preservation of 
stall manure, but their value for this purpose is perhaps over-estimated. 
24. Potash fertilisers should, asa rule, be applied in the autumn, or at 
least from two to four weeks before planting, and should be thoroughly 
worked into the deeper part of the soil in order to come into contact with the 
rootlets of the piant. 
25. The germination of seeds, especially if they have a low vitality, is 
retarded by bringing them into direct contact with potash salts. apt 
26. The application of crude potash salts to a soil which is not easily 
cemented may he useful during a dry season by reason of their power of 
attracting and holding moisture. 
27. Potash salts favour the decomposition of mineral particles in the soil, 
. and thus tend to add to the stores of plant food therein. 
28. The application of crude potash salts to the soil tends to protect the 
crops from frosts by preventing the too rapid evaporation of moisture, and by 
producing a more luxuriant foliage. 
29. The too abundant application of potash to the soil may become 
injurious by reason of the retardation of the process of nitrification which it 
produces. 
30. Crude potash salts, especially kainit, when added abundantly to a 
soil, are said to act, to a certain extent, as an insecticide or a preventive of 
disease, and when mixed with stable manure act as a preservative by checking 
the activity of the denitrifying ferments. 
31. It is ie aecable to give formulas for the preparation of fertilisers 
containing potash, since both the quantity of potash to be used and the form 
in which it should be applied are determined by local conditions, which cannot 
be taken into account in the preparation of directions for the use of fertilisers. 
