FARMING PROBLEMS IN CANTERBURY.

New Zealand Journal of Agriculture, Volume XXXVIII, Issue 2, 20 February 1929, Page 92

FARMING PROBLEMS IN CANTERBURY.

CURRENT RESEARCH WORK OF THE FIELDS DIVISION.

A. H. Cockayne,

Director, Fields Division, Department of Agriculture.

Apart from general instructions and advice on better farming methods, the Fields Division is carrying out a large volume of research. and investigation work on farming problems in Canterbury. For practical purposes this work can be divided into four main divisions as follows :— (1) The most profitable manuring for grain, fodder, and potato crops. (2) The demarcation of soil and pasture types on which top-dressing is likely to be payable. (3) The elimination of diseases and pests in grain and other crops. (4) Improvement in crop-production by the utilization of superior types, and by means of crop certification.

Improvements in Manuring of Crops.

WHEAT.

Manurial work with wheat is now in its fifth year, and with increase in opportunity the operations this season have expanded considerably. There are twenty-seven series of experiments on farms in Canterbury and North Otago. In each various forms and quantities of phosphate are included. The main objective is to determine what phosphate and what amount is most profitable to use, leading, with an extension of the present programme, to the demarcation of the high and low phosphate-response soils as they exist over the wheat belt.

From the experiments conducted up to the present it has been shown that 1 cwt. of superphosphate on the average increases the wheat-yield from 4 to 5 bushels per acre, and is in general highly payable, but that there are areas where no significant increase can be recorded. The most important result from the work has been the demonstration that high phosphate-response is just as regular on the 60- to 70-bushel crop as it is on the 25- to 30-bushel yield ; also that high response is likely. to occur equally whether the prior crop has been a harvested one, a fed-off green crop, or roots. Before work was commenced in Canterbury, wheat after rape was rarely manured, yet many of our most significant increases have been secured where the prior crop was of this type.

One of the main difficulties against a rapid extension of this important work is the problem of the harvesting of a very large number of plots. The cereal investigation projects that have been laid down this season necessitate the separate harvesting and weighing of over six thousand plots, and in order to secure efficiency adequate apparatus is necessary. In past years a small mill driven by a tractor has been used, but this season a special easily transported threshing unit has been devised that will enable all the plots to be harvested accurately and expeditiously.

Until quite recently it was not considered that nitrogen in increasing the yield of wheat was likely to be profitable, but the work under this project has shown that nitrogen top-dressing in the spring, in addition to phosphate application at the time of sowing, is likely to be a sound manurial practice. Last season over a number of trials nitrogen in the form of nitrate of soda at the rate of i cwt. ' per . acre increased the wheat-yield by 6 to 7' bushels per acre over and above the 4- to 5-bushel increase secured through phosphate. This season some twenty-five carefully conducted experiments with nitrogen are being carried out, and in addition some three hundred demonstration areas have been top-dressed. Experiments also as to the relative effects of various types of nitrogen have been laid down.

If this season’s results again demonstrate that nitrogen top-dressing is likely "to be highly payable, experiments on amounts, kinds, and time of application will have to be undertaken. The fact that in a great number of instances phosphate-manured wheat has in the spring the typically pale coloration indicating nitrogen starvation is being taken by the Division as a pretty clear indication that top-dressing such crops with nitrogen would be a payable practice. An element of uncertainty lies in the fact that- extensive nitrogen work with wheat has been largely confined to the past two seasons, both of which may have been particularly favourable to nitrogen response. However, the fact that for three seasons in succession payable increases have been recorded on one particular farm would seem to indicate that seasonal factors were not the definite cause of high response..

TURNIPS.

In the drier parts of New Zealand super has been shown to be the best phosphate for turnips up to 1 cwt. per acre. Above this amount its solubility is apparently disadvantageous, and its depressing effect on germination serious. The standard Canterbury dressing of 1 cwt. per acre has been shown to reduce germination by some 20 per cent., and 2 cwt. per acre reduces it by over 50 per cent. This refers particularly to Canterbury, where one-third of our turnip crop is grown, but germination injury is common throughout. Bad effects on growth always follow germination injury. The methods under trial to overcome injury are (1) pre-drilling portion of the manure, (2) post-drilling portion of the manure, (3) reversion of the super by mixing it. with lime.

The use of lime with super has increased the germination in certain cases by 50 per cent., and the yield by 20 per cent, in some instances. Much requires to be learnt regarding the amounts of lime to use and when it should be mixed. Mr. W. D. Reid, in connection with his legume nodule organism work, is working out a clever method of testing the injurious effects of manure, using the nodule organism as the indicator.* This will enable a drastic reduction to be made in the number of treatments necessary to test in the field.

Methods whereby heavier applications of phosphate may be safely used will be of the very greatest value throughout the whole of

Canterbury, and this work can perhaps be viewed as being one more pregnant with immediate possibility than almost any other undertaken.

RAPE.

Four years’ work in Canterbury with phosphate has definitely shown that the slow-acting phosphates by themselves are definitely inferior, but when used in combination with super the results are far superior to where super alone is used. Nitrogen has increased the crop by 25 per cent., being payable on good crops, but not so on poor ones. A large number of trials are being conducted this season.

POTATOES, ETC.

The work carried out indicates that increases of from 1 to 2| tons of table potatoes are secured with 3 cwt. of super; in fact, the manuring of the potato crop is the operation which shows the greatest profit, and at the present time it is the one that is -most neglected in this respect. ' • • So far as other annually sown harvested crops are concerned, such as barley, oats, peas, linseed, &c., no properly planned work has so far been attempted.

INCIDENCE OF MANURING.

In order to secure fairly reliable information regarding the amount and incidence of cereal and other crop manuring (information of great value in planning experimental location) it was arranged with the Government Statistician for such information to be included in the acreage sown” cards that he sends out each spring. The results of this collection are of distinct interest. Of the 200,000 acres of wheat in Canterbury this season some 130,000 ' acres have been manured. Out of 130,000 acres of oats, 75,000 acres have been manured, and out of 11,000 acres of potatoes less than namely, 5,000 acres have had manure applied. ‘ These figures indicate that the Canterbury farmer is by no means taking full advantage of the profit resulting from rational manuring, and show the necessity for extended demonstration. It is safe, however, to say that the comparatively large areas of cereal crops which have been manured are a direct reflection of the extended experimental work that the Division has carried out.

Demarcation of Soils and Pasture Types on which Top-dressing Response is likely to be payable.

Some two hundred distinct top-dressing trials to be carried out over a series of years were laid down during last season, and these should give extremely valuable information. . Owing to the small response from top-dreassing on much Canterbury land, renewal of pastures to keep up an adequate supply of young and vigorously growing grass will have to remain on such land an integral feature of management. But it» is essential to find out on what soils and under what conditions top-dressing will enable grassland to remain essentially young in character longer than at present. In many cases at present pastures are old and useless for rapid milk- or meat-production at' the end of the third year or earlier. Where top-dressing is payable the tendency must be to extend the profitable, life of pastures, but where it is not so an increase of cropping leading to more rapid renewal of grassland

would appear sound. At the present time less than i per cent, of the sown grassland of Canterbury is top-dressed. This is in striking contrast to the 85 per cent, that is annually top-dressed in Matamata County, in the North Island. Phosphate responses in parts of Canterbury are highly satisfactory, but in others they are not payable, and the work now being undertaken should enable the Division to say with far more assurance than at present when and where top-dressing should become a regular practice.

Elimination of Diseases and Pests in Grain and other Crops.

Perhaps the - most significant achievement of the Fields Division in the past five years has been the brilliant .work of Dr. G. H. Cunningham in demonstrating that a large number of our most serious crop-diseases are seed-borne, indicating the importance of using seed that is free from disease. A very great deal of work has been and is being conducted along the line of seed-treatment, and with regard to the barley crop several serious diseases have been more or less eliminated from considerable areas of New Zealand. The control of seed-borne diseases represents the major line of attack that is being made. by the mycological specialists of the Division, and this is very closely connected with certain phases of crop certification, the final objective being an adequate supply of disease-free seed to be made available for all farmers.

Another line of research that is being actively prosecuted at the present time is the control of certain insect pests, notably turnip-aphis and diamond-back moth, both of which seriously limit the optimum production of the- turnip and rape crops in Canterbury. Here biological control by the use of natural enemies appears to be the most hopeful line of action, and a thorough study of all known natural enemies is being made by the entomological staff of the Division.

Superior Types and Crop Certification.

The Agronomist in charge of this work is using the method of crop certification as the basis on which the whole of the work finally hinges. The final objective of certification is to enable farmers to secure reliable seed true to type and disease-free. It is not to be expected that strains absolutely true to type and free from disease can be made available immediately ; but this is no reason why crop certification should not be put immediately into operation, enabling the hall-marking of the reasonably pure and reasonably disease-free crops as against what may be termed the “ scrub ”, crops of the country. Ability on the part of the farmer to secure “ certified ” seed representative of the best crops in the country, rather than. perhaps the worst, will be of enormous advantage. The very considerable success already following the initial work in potato and wheat certification has shown conclusively that crop certification is as important in crop-production as herd-testing is in milk-production.

Certification of crops as they exist can be put into operation just as fast as it is known what characteristics should be certified to, and whether-the certification of certain characteristics is a reliable guide

to the superior qualities of any crop. In the securing of such knowledge an immense amount of work is . involvedin strain selection, experimental and field testing, ascertaining of disease resistance, disease treatment, and a host of other considerations. At the beginning certain assumptions have had to be made, and these and any further assumptions have to be proved or disproved by accurate trial and investigation. The case of the potato may be taken. It has been assumed that with regard to any particular variety the best crops are those that contain few rogue plants and are freest from disease. Certification so far has been based on this assumption, but there is also the assumption that certain strains within any variety are better than others, and that the. presence of certain diseases is far more objectionable than the presence of others. These assumptions have all to be studied, and by the final production of the best types of pure line strains, free from any diseases of moment, it is hoped to achieve great improvement in the crops. Certification is to be used to segregate the better from the poorer crops at present grown, and later on it will also be able to retain the identity of. any new' strains, or any crops that are free from diseases that are carried in the seed.

Again, there are certain assumptions —particularly true with regard to grasses and clovers —that crops in certain districts and under certain conditions of management produce better types of seed than others. The actual isolation of special types and their thorough testing is a matter that may take many years ; but there are some points with regard to certain grasses and clovers which could rapidly be put under certification. The value of such certification could be tested, and if found reasonably sound could continue until such time as definite specially selected and tested strains were available for certification. The following are examples of such types of temporary certification ; some are to be put on trial this season : (i) Cocksfoot certified to be from pastures over ten years old; (2) white clover certified to be from pastures over twenty years old ; (3) brown-top certified to be free from red-top ; (4) red clover certified to be from crops that have been harvested for seed three or more years in succession ; (5) red clover certified to be free from dodder ; (6) Hawke’s Bay rye-grass certified to have been produced in Hawke’s Bay or Gisborne.

It is perhaps not generally realized how greatly the agricultural instruction and research work of the Fields Division has increased, Canterbury during the past six years. There is now a staff of eight under the control of Mr. R. McGillivray, Fields Superintendent. In addition, the Agronomist, Mr. J. W. Hadfield, and his staff are located in Canterbury, while much of the work of Mr. A. W. Hudson, Crop Experimentalist, Dr. G. H.- Cunningham, Mycologist, Mr. J. C. Neill, Field Mycologist, and other officers of the Plant Research Station of the Division is concerned with research and investigation into problems that are particularly concerned with the future progress of Canterbury agriculture. Finally, much useful co-operation is being maintained with other bodies or institutions concerned with the agriculture of the province, such as the Canterbury Agricultural College.

* See article by Mr. Reid describing an experiment with lucerne - seed, page 103 of this issue.—Ed.