LIME.

Pukekohe & Waiuku Times, Volume 4, Issue 3, 12 January 1915, Page 4

LIME.

♦ I Its Uses and Value. It is one of the advantages of liming the soil that the lime haa a chemical action, disintegrating the v mineral constituents in the soil, c and thus rendering available for 1 plant nourishment the soil potash \ and phosphate which would other- i wise remain inert. For this reason its application this ] season is especially appropriate, i because its action will release soil I potash," and thus help to make up I tor, the lack of the ordinary com- I me'rcial potash. 1 Liming the soil was a general j practice half a century agu, but its ! use has beccome less general, i There is, however, evidence in many ; parts of the country tfct, apart from the above consideration, appli- i cations of lime sre becoming i essential, and although it may not bs neassary to revert to ihe old practice of suca tuavy dressing as 6 or 8 tons to the acie, it is probable that smaller dressings of about a ton to the acre, app'ied once in the courte of each rotation, would be attended with good results, eeecially in heavy soils. There are several kinds of lime, and farmers must use their judgment as to which is most suitable for their individual requirements; their choice will depend en local circumstances as to supply, the nature of their lands, and the needs of the crops. THE KINDS OF LIME. Quick Lime and Slaked Lime.— Ihe most common form of lime is that known as burnt lime, lime shells, quick or caustic lime. It ahaoros water very rapidly, becoming then slaked lime; it also takes up carbonic acid gas from the atmosphere, forming then carbonate of lime, similar to chalk or limestone. It should contain 85 per cent of quick lime, and farmers should insist on a definite guarantee. According to the report* of the analysts to the different agricultural societies, there is a lot of tow-class lime told to tarmers, and therefore it is necessary to be careful when buying. Ground lime is the burnt lime ground to a fine powder, which is more convenient to apply, and recommended as more economical to use, but it costs in bags 8s to 9s more per ton, so it is for the farmer lo judge whether it is worth the extra money. Ground limestone is coming more into use, especially for meadows and pastures. It is easy to bundle, and is cheap. It should contain 90 to 95 per cent of carbonate of lime, and 1£ tons is equivalent to a ton of burnt lime. Gas lime is a by-pro3uct in the manufacture of coal gas. When obtainable at a vtry low price near the factory it is worth buying for application to heavy lands, which it helps to break up. As it contains some poisonous substances it should be spread on the land seme weeks before ploughing. ADVANTAGES OF LIME. 'ihe benefits to be derived from applications of lime to the soil are well known, and may be summarised as follows: 1. It acts directly as plant fuod. 2. It cures sour land, acd by so doing improves the herbage when applied to grass land. 3. It prepares the locked-up vegetable matter of the soil for plant food by liberating trn nitrogen wh'ch it contains. 4. It decomposes the dormant mineral fcod of the soil by splitting up the silicates and liberating the potash. 5. It improves the physical condition of heavy clay land. It ensures the complete utilation ni soluble nhosphatic manures and of sulphate of ammonia, and in so dning prevents any possible injury to the crop by an e.\cess of acid used in the manufacture of purchased artificial manures. INFLUENCE OF FERTILISERS ON LIMrJ IN THE SOIL. There is a continual loss of lime from the soil. Thus at Rothamsted, where the matter has been carefully watched for a number of vears, it is calculated there has been a lobs of half the original stock in the soil. Artificial manures have a certain effect on the rate at which the lime is washed out. This has also been investigated at Rothamsted, with the following results:— Superphosphate, sulphate of potash, kainit and similar manures do not increase the loss to any appreciable extent. Farmyard manure, and probably all organic manures, diminish the loss. Nitrate of soda diminishes the I'jss. Sulphate of ammonia increases the loss, removing about half its own weight of lime, or nearly its own weight of chalk. Therefore, sulphate of ammonia should never bt applied to land which dues not contain an ample supply of lime. APPLICATION OF LIME. Lime being applied for many purposes, the proper quantity to apply may vary accordingly to the purpose for which it is applied. Ordinary dressings are from 2 to 3 tons of quick lime at intervals of from six to ten years. Smaller dressings of from half a ton to a ton given more frequently are now becoming common. Large quanti ties may be employed with advantage for newly reclaimed land rich iu organic substances. Ground lime being more evenly distributed may be applied in smaller quantities. Ground ' limestone— l ; l tons is equal to a ton of quick lime. Gas lime. —A dressing is 2 to 4 tons per acre. It should be spread | over the land about six weeks before ploughing.