USE OF FERTILISERS

Taranaki Daily News, 29 December 1934, Page 20 (Supplement)

USE OF FERTILISERS

SEASONAL REQUIREMENTS ROTATIONAL MANURING. Most of what is written and a good deal of what is spoken concerning the use of fertilisers deals with what may be termed the technical side of the practice, said Mr. W. Alexander, agricultural adviser to Kempthorne Prosser and Co. Ltd. Experiments conducted by the Department of Agriculture and lectures delivered by various experts are designed primarily to show the necessity for adding phosphates, potash, calcium or nitrogen to the soil, and in the main the information as supplied has been valuable; as a matter of fact, most of our present day knowledge concerning the use of fertilisers originated from the experimental stations and the laboratory. Farmers are asking themselves three simple questions; these questions I would state in this way: What does my land require? How am I to put it there? When should I put it there? Briefly the answers are: Your land requires calcium, phosphates, and nitrogen and potash; you put these plant foods in by applying lime, superphosphate and 30 per cent, potash salts, and you make these applications at frequent intervals throughout the year so that there will always be a supply of feed coming on. In the first place it has been very definitely established by every test at our disposal that calcium and phosphates are the universal soil deficiencies throughout New Zealand, and it is now further demonstrated that potash is also deficient in a greater variety of soils than was at one time admitted. Other deficiencies exist in more or less defined areas, but to the great majority these other deficiencies are not important; in any case even in such areas as that known as the pumice belt, where iron is an important deficiency, there exists the same universal need for calcium, phosphates and potash. If we look beyond the immediate needs of the soil itself, and direct our attention to the products of the land, we still see the same outstanding need for calcium, phosphates and potash. These minerals are continually being removed in the form of butterfat, meat and wool, and it is these same minerals that must be returned to the soil. Now we can be quite positive about this universal need and we can be just as positive that this need can best be met by applications of lime to supply calcium, super to supply phosphate and 30 per cent, potash salts to supply potassium. Actually the fertiliser requirements of this Dominion are exceedingly simple as all the essential materials are easily obtained, easily applied and comparatively inexpensive. STANDARD PRESCRIPTION.

I have no hestitation in saying that the dairy farmer who applies scwt of carbonate of lime per acre every second year, and who then uses a dressing consisting of 2Acwt of super and lewt of 30 per cent, potash salts every year on his grassland will come out right every time.

I do not suggest that this programme is complete for all conditions of soil and climate; whait I would convey rather is that such manuring practice is sound and the ingredients used are designed to supply those minerals that everywhere are most in demand—in other words, this type of manuring is at once foolproof and . productive of results. Lime should be applied in scwt dressings on one half of the farm one year and on the other half the following year, and thereafter in the same order so that every acre receives the equivalent of each year. Here you have the practical interpretation of all the scientific work so far carried out concerning the use of lime. With the top-dressing mixture, buy the ingredients separately and mix them as you sow them. There is no chemical reaction required between the two minerals—the super and the potash—each is complete in itself and each- is complementary to the other. A matter of great importance in connection with this mixture is the time of application. ONCE-A-YEAR-METHOD. Let us look back a few years—when fcrtiUsers were first used to any marked extent it was for sowing with annual or seasonal crops. Later, the application of fertilisers to grassland became popular and was adopted as a spring-time task. The fcri.il tsars used—mostly super—acted quickly and certainly gave results that were so obvious as to be apparent to the most sceptical It was soon realised, however, that this extra spring and summer growth brought with it added difficulties in the way of increased stock that had to be wintered later on or increased acreage that had to be cut for hay or ensilage. Experiments demonstrated the ability of these same fertilisers to produce extra growth if applied in. the autumn, and this was hailed, as the solution of the winter feeding problem. Gradually theft? was a swing-over to autumn top-dress-ing, and this practice became more universal when it was found that autumndressed pastures were always the first away in the spring. Now we have the latest development of twice-a-year applications becoming more pronounced. I would say that the man who de-; pends upon a simultaneous manuring over the whole farm once a year is not getting anywhere near the maximum benefit possible from fertilisers. It is not possible to conjure up extra stock just when it is most required and the actual results of this practice of simultaneous manuring are (1) increased areas to cut or feed will be going to waste, (2) lowered feeding value of grass which in turn is reflected in lower production figures or loss of condition in stock and (3) permanent injury to pastures. Most of these conditions could be avoided if applications of fertilisers were “spread” over the year instead of being concentrated in one effort. No man would consider it good farming to give his stock one good feed, say, once a month and then let them starve in between times, and I see no more reason why you should give the whole of your farm one good dose of super and potash and then leave it alone for a year.

The tendency to-day is to make ’the application of manures too rigid a practice; a sort of once-a-year job that has to be done something like shearing or haymaking. Fertilisers should be looked upon more in the nature of reserves of labour to be brought into action as circumstances warrant and at frequent intervals. We speak freely of rotational grazing—l would have you speak just as freely of rotational manuring. ON THE DAIRY FARM. Take the case of a dairy farmer who has cows coming in in July or August and who expects then to milk through until May or June of the following year —he has what may be termed four periods calling for special consideration. His first requirement is grass in JulyZ.ugust; all right, he must go back at least a couple of months and make his application of super and potash or if he prefers, ammoniated super over such area as will keep his cows going until the October growth starts in earnest. From October until January there will be plenty of grass without the direct aid of fertilisers, but during this period he must make provision for next winter’s supply of hay and ensilage. He decides to close up the required number of

paddocks and before doing so he gives them a really severe harrowing and an application of super and. potash. The next period for consideration is the dry weather following the New Year when the feed position becomes serious, unless special provision has been made beforehand. Here again is an opportunity to let the super-potash mixture do its work. At the end of November topdress as many paddocks as will be required to keep up the grass feed supply over the dry spell. This application must be made by the end of November or the first week in December as some moisture is necessary in the soil if the fertiliser is going to do its work. Then comes the last period calling for special attention, namely late autumn and winter. If the winter carrying capacity is going to be assisted by fertilisers, and it can be, then the application must be made about the end of February or March so that there will be grass for May and June. Now we have a programme that calls for a fertiliser application in May-June to provide grass in July-August. September-October to ensure heavy hay and ensilage crops. November-December to provide for dry weather after New Year. February-March for winter feed. ■