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to winter and autumn dressings, as these gave most promise in last year's trials. A full report on these trials will be prepared during the coming winter. The winter dressing, about July in the North Island, has given varying results. These may be viewed as satisfactory in the majority of cases, especially where good rye-grass and cocksfoot are plentiful in the sward. In some cases the nitrogentreated fields tend to dry up rather more than those without nitrogen during dry summer weather. The mowing trials at Marton confirm this, where nitrogen is applied without some phosphate at the same time. About half the trials will be continued in the coming season. It is difficult to interpret the results in terms of pounds, shillings, and pence, and it appears that this can be done only by running two similar farms under intensive rotational grazing. Both farms would have to be managed the same, mineral manures being used on one farm, and minerals + nitrogen on the other. Careful costing would be essential. The present system of trial does not give any measure of the indirect value on subsequent production of the production and feeding of grass at periods of normally low production. (2) Dairy-farm under Intensive System.—A report on the intensive grass-farming of Mr. J. Ward's farm, Manawaru, was published by Mr. Woodcock in the Journal of Agriculture for October, 1929. The report showed the effect of properly controlled grazing in prolonging the peak of lactation. The production of butterfat reached a very satisfactory figure of 212J lb. per acre in spite of adverse conditions during the early part of the season. A full examination will be made this winter of the difference in production between the phospliated fields and those treated with phosphate + nitrogen. (3) Grazing Trials to determine the Relative Merits of Hawke's Bay Perennial Rye-grass and so-called Canterbury Perennial Rye-grass in Canterbury. —The work of the Agrostologist has demonstrated very clearly the advantages of true perennial rye-grass so far as persistence is concerned. It is of vital importance to get true perennial rye-grass sown throughout New Zealand, and in order to get some measure of its value relative to the strains normally sown in the South Island, arrangements have been made to carry out six grazing trials on various soil-types in Canterbury. The work is being done in collaboration with the Agrostologist. Two trials have already been laid down, and others will be sown in the spring. The fields will be managed under the intensive system, and records of stocking kept for several years. (4) Observational Top-dressing of Pasture.—About 430 trials of this nature are under way. About 140 of these are in the North Island, and represent the trial and demonstration of the effect of manures according to district requirements. In Canterbury-Marlborough 240 trials and in Otago-Southland fifty trials are in progress. These are mainly experiments in which lime, phosphate, potash, and nitrogen are used. Most of the Canterbury series were laid down in the winter of 1928, and constitute a survey of the country to determine the chief limiting factors in pasture-production. These trials have been highly successful in indicating several important features, the chief of which are — (а) Lime is of extreme importance in something like 90 per cent, of the areas under trial. There can be no doubt regarding its economic value even at the present unreasonable price on the majority of Canterbury lands. The light lands of low rainfall have responded to an unexpected extent. The efficient production of ground carbonate of lime, which would result in its being available to farmers at about 12s. per ton (as in Southland), is urgently needed in Canterbury. (б) Superphosphate has given good results (except on some of the very light lands), especially on limed ground. (c) Potash appears to be of little general value. In a few cases it has shown slight improvement of the pasture on limed ground. It has practically no effect on unlimed ground. (id) Nitrogen is of extreme importance, and has generally improved the sole of grass where used in conjunction with lime and phosphate. Its economic value must be the object of further investigation in the near future. The information obtained from these trials points clearly to the desirability of an experiment-plot survey of New Zealand. Experiments so far conducted outside Canterbury have demonstrated the fact that there are soils which are markedly deficient in potash, amongst other things, and it is necessary to get a manure-response map of New Zealand prepared as soon as possible. Arrangements have been made with the Director of the Fields Division for this work to be started. Unfortunately, stafflimitations prevent the scheme being fully launched at once, but a start is being made by getting about ten trials distributed over each Instructor's district. Further work in the South Island must be closely associated with the trial of manures on pastures sown with better and more perennial species than are being used at present. It is almost impossible to select a pasture which is reasonably good after its first year. This is particularly the case where so-called " perennial " rye-grass is the chief species sown. (5) Haying Trials. —These are not being extended, and at present six are being carried out in the North Island, four in Canterbury, and fifty in Otago-Southland. The measurement of production in these trials occurs during the high-production period, and, as this is the time when" production usually looks after itself, there seems no particular object in continuing this class of work, except where manuring is done specifically for the production of hay or silage. DISCUSSION OF EXPERIMENTS UNDER C. Experiments on Annual Crops being carried out by Fields Officers. (1) Wheat. (a) Manuring.—(i) A comprehensive series of manuring trials, consisting of twenty-five experiments in Canterbury and Marlborough and six in Otago, was laid down and carried to a successful conclusion. The trial of superphosphate, muriate of potash, and nitrate of soda was continued. In addition, a number of trials with 1 cwt. and 2 cwt. of super, with and without nitrate of soda, were sown. The general results are as for previous years so far as the first-mentioned manures are concerned. The

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