FASHIONS IN FERTILISERS

Shannon News, 25 October 1927, Page 2

FASHIONS IN FERTILISERS

"OLD" AND "NEW MODELS,

SOME RECENT CHANGES,

"That agriculture, our oldest industry, follows ficMe fashion like any of the despised luxury trades may not be generally realised," states a writer in the "Fertilisers' Journal."

The thought is not altogether a new one, although as suggested, it may not be widely readised. One has only to look backwards over a few decades to realise the changes that have taken place in fertilising practice. Going back to the days when artificials were unknown, we read that farmyard manure was generally applied for all crops. Since then the wordl's scientific men have been working to discover substitutes that are at once easily procured, easily applied and inexpensive. Just how well they succeeded is well known and one is tempted to say that there cannot be much use in trying a new fertiliser that will work wonders by growing bigger and better crops, while reducing costs, etc.; propaganda work that may be responsible for the changes that one made from one fashion to another. The Cult of Basic Slag.

The groat basic slag fashion, originating I'voni the mighty slag heaps of the industlial North of England, has been one of the hardiest. Supported, as it was by wealthy industries, despairing of an adequate dumping ground for their refuse, and backed by mighty pronouncements from official experiments, the cry of "basic slag" spread throughout the land until in some districts the words basic slag and pasture seemer wellnigh inseperable. Not that there was no merit in the new fashion —far from it. Grassland which had been neglected for years even for centuries, had become impoverished and lacking in phosphates This poverty was all the more noticeable on those lands which had been

heavily dunged each year—a practvo. still followed by many northern dairy farmers. Thus these grasslands became more and more acid and heavily charged with nitrogenous products most of which were inevitably wasted both by decomposition and because the unfavourable soil conditions tli'ii:* produced would not permit ot a

healthy growth of grass. Here, too, the inexorable law of

!.h9 minimum came into operation. Every' plant, including clovers, requires for its successful., grow Ih an

adequate supply of nitrogen, phosphales and potash, and generally sneaking, within certain limits, wll 'VrOw in proportion to the amount of r -ach supplied. Should, however, o.v of these elements be missing or deficient in proportion to the other two, then the growth must bo restricted by the amount of the element present in the smallest quantity.

It is easy to sec, therefore, how these ancient grasslands which had been continuously manured with animal excreta rich In nitrogen were really suffering from phosphate starvation. Hence the truly marvellous results which followed a dressing by

slag in many places. Superphosphate.

The greatest rival to basic slag slag- arose in superphosphate and even now thfs addition to" science is the most popular form of soluble phosphate. The advantages claimed for superphosphate are (1) its complete independence of tire ups and downs of the steel industry upon which our supplies of basic slag depend; (2) its evenness of grade; (3) its higher content of phosphoric acid; (4) its suitability for all crops, including grass; (5) its rapid action in the soil. Each and every one of these virtues helped to establish its place on the world's markets.