Rationed Fertilisers

New Zealand Journal of Agriculture, Volume 64, Issue 2, 16 February 1942, Page 81

Rationed Fertilisers

Best Utilisation Should Be Made In . Topdressing Season

Not the least of the problems to be faced by farmers as a result of the war is how to utilise the fertiliser available during the coming topdressing season. The rationing of fertilisers was unavoidable, and attention must now be directed to ensuring that the effects of this restriction are reduced to a minimum.

JUiuiini By iiiiiiiiimuiiimiiiiiiiiiiiimimiiuiHiiiiii.

I. L. ELLIOTT,

I Supervisor of Fertiliser i I Supplies, Wellington. I = ' < ’ = jßaiiiiiiiitiiiiiiiiiiiiiiiiiiiniiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiaiiiiiß i ( ' A -i 1 " ‘ r ‘ [ ( - . s '

r T- , HE first point which must be carefully considered is must be carefully considered is the type of fertiliser which should be purchased. In addition to straight superphosphate, considerable publicity has been given to the use of serpentine superphosphate, to the use of reverted superphosphate, and varying mixtures of superphosphate and lime. An article setting out the ' advantages to be obtained from the use of serpentine superphosphate appeared in the September issue of. the “Journal,” and it is only necessary to reiterate that the majority of farmers would obtain considerable benefit by purchasing , serpentine superphosphate in place of superphosphate. The general conclusions to be drawn from the data presented in that article were that 3 cwt. of superphosphate was no better on the average than 3 cwt. of serpentine superphosphate. As a farmer is entitled to obtain 1 ton 8 cwt. of serpentine superphosphate for every ton of superphosphate to which he is entitled under the rationing scheme, it will

readily be seen that considerable advantages are to be obtained by purchasing the former material. If, therefore, 3 cwt. of superphosphate is no better than 3 cwt. of serpentine superphosphate, the extra 8 cwt. of serpentine superphosphate which can be purchased is as good as a further Bcwt of superphosphate. r . Increased tonnages over the . superphosphate allocation are also available for \ superphosphate-lime mixtures, and in many districts superphosphate-lime mixtures give better results than superphosphate alone. A feature of buying these mixtures, which are put up in the manufacturer’s works, is that the farmer has to pay railage of lime into the works, together with a mixing

charge, blit this extra cost is often unnecessary, particularly in districts where copious supplies of lime are available locally. There are many difficulties in mixing the lime with superphosphate on the farm, particularly with the present labour shortage, and many farmers will prefer to pay the extra cost rather than attempt the mixing themselves, but, where possible, there is an obvious advantage in purchasing superphosphate and mixing the lime with it. In addition to using lime in mixtures with superphosphate and other materials, the present time is ideal for . the extended use of lime alone, and as much lime as possible should be used to replace the annual dressings of superphosphate normally applied. If this advice is followed, it is almost certain that better responses from phosphatic fertilisers will be obtained when they become once more freely available.

Topdressing Season

The normal season for topdressing grassland, particularly in the North Island, is in the autumn, and in order, to avoid waste, farmers must consider applying whatever supplies of fertiliser are available at the optimum time. No

hard and fast rules can be laid down, but it can be said with ' certainty that applications should be made sufficiently early before the cold winter weather sets in to obtain an . increased growth from the plants. This will invigorate the pasture, enabling the full exploitation of added phosphate, and will thus make possible highest pasture production throughout the winter months. Normally, the winter is the period of least grass production, and it is therefore to these months that most attention must be given if it is desired to increase or maintain the carrying capacity of a pasture. It has already been pointed out that the best time of application can be determined only by the farmer himself, as even within a radius of 30 or 40 miles considerable variations in climatic conditions may be experienced. Over a /considerable portion of the North Island applications have, in the past, been made too late for best results to be' obtained, and while there was some justification for this when manufacturers were experiencing difficulty in obtaining the necessary supply of trucks to make deliveries, with limited quantities of fertilisers available no undue difficulty should be experienced in obtaining supplies at the correct time. However, in order to make sure that supplies will be available ■■ when - required, farmers should

arrange to place their orders early and, 1 if necessary, store before application. Because of the cutting off of normal continental supplies of potash fertilisers through the war, a shortage in some types has arisen, mainly in supplies of. the favourite 30 ' per cent, potash salts, but there are available in the country supplies of muriate of potash, which could possibly be used in areas such as Waihi, Taranaki, and South- - land, where a known potash response is to be found. The ex store price of this material is, , however, £3l 5s per ton, which will be, in most cases, 1 too dear for the average farmer to' use for topdressing purposes. It must be pointed out, however, that ' the muriate is twice as valuable as the 30 per cent, potash salts, and that on the basis of 30 per cent, potassium oxide (K 0 the price asked would be £l5 12s 6d per ton.

Blood and Bone Restricted

Regulations were recently made restricting the distribution of blood and bone and organic fertilisers. One of the many reasons for this has been that the restricted supplies of phosphatic fertilisers have increased the demand for this commodity, leaving a short supply for market gardening requirements, which are regarded as being of first importance in the feeding of the Dominion’s population. Broadly, the regulations provide for priority to be given to market gardeners’ orders, but as it is expected that we shall produce about 20,000 tons of blood and bone, and ■as only ' 6000 or 7000 tons will be required for market gardening purposes, there will be a substantial surplus available for use on farms. It is as well to point out, however, that blood and bone should not be used for sowing down with a pasture mixture, as germination injury is likely, but, where available, it is most useful for topdressing. In present circumstances, it is felt that although good results will be obtained by using blood and bone for topdressing, by far the larger proportion. of this material should be used on crops.' / Coincidental with the increased demand for blood and bone, the demand for bone dust has . also greatly increased, and, there must be many places in which valuable supplies of bones are wasted. Farmers and others concerned would do well to bear in mind the value of these bones, and where quantities justify such an action, they should be saved and either used by the farmer himself on his own farm

or forwarded to some purchaser for conversion into bone dust. There are many registered country slaughter houses throughout the country which, if taken in combination, should contribute a considerable amount to the available supply of bones.

Where to Apply Fertiliser

Probably the most important decision to be made by the farmer is where to apply the fertiliser with the smaller quantity available than in previous years. Here again, no hard and fast rule can be laid down, but the best results will undoubtedly be obtained if the fertiliser is applied where pastures are the best and .where soil types

are known to respond. A corollary io this is, therefore, that farmers should not apply fertiliser in any place where a response is, at best, doubtful. Where pastures have been sown down, it will do no harm to reiterate what has been said many times before, that to obtain the best use of phosphate or other fertilisers, the best seeds and the best possible cultivation and pre-working of the land is necessary. Where control of weeds is a factor, attention must be given to all phases of grazing management with the .object of controlling by the efficient use of stock those areas which cannot be topdressed. ; , ’ - A method of improving the fertility of some paddocks which has all too frequently been overlooked is the feeding out of hay or silage into these paddocks, when the materials returned by the grazing, animal to the pasture will, if harrowed, materially assist in maintaining and increasing its productivity. As livestock . are the ultimate converters of phosphate into saleable products, more and more attention should be paid to the efficient use of

the grazing animal, which will assist in conserving our already , depleted supplies of fertiliser. In recent years, particularly in overseas countries, considerable attention has been directed to placing fertiliser in such a way that best results are obtained. With the ridger and the drill, a fairly efficient type of placement is normally effected. With topdressing, it yet remains to be seen whether our present methods are the best which can be devised, but in present circumstances, with the material available, it is the best which can be put into practicable ' application.

Establishing Grass

Much has been said and written at various times on the best method of establishing grass, and although it is realised that the limited supplies of fertiliser available for sowing down grass after crops is probably insufficient for absolutely ideal pasture establishment, farmers should consider whether or not they are prepared to

use a portion of the fertiliser allocated for topdressing purposes for the treatment of newly sown down areas. As, in most cases, the pasture has to last for many years, the best possible treatment is necessary to ensure its permanency, and it may well be worth while to omit the topdressing of some wellestablished pastures in order to build up and thoroughly establish any new areas. Although variations will be necessary to meet individual cases, the best results are, on the average, obtained where fertiliser is sown with the seed and where ' this is followed up at a later date with the topdressing of the newly sown grass. It is fully realised that, as a result of present conditions, many new problems will be confronting farmers, but in the majority of cases some compromise between the ideal and the practicable will have to be made. Attention should be focused on seeing that this compromise is the best possible one that can be made in the circumstances.