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Further investigations into the role of fineness of grinding of limestones in rendering them soluble in the soil have enabled tentative conclusions to be drawn as to desirable standards for commercial products. As this is an important matter both for farmers and lime companies, some very carefully controlled field trials have been put down to check the results of pot experiments and laboratory methods before attempting any modification of existing procedures or standards. Lime and molybdenum have been found by soil investigations in various countries, notably Australia, to be closely interrelated in their reactions in the soil and plant. In Southland very heavy lime applications have been common practice for a number of years and it was thought desirable to check the effects on soil reaction, lime content, and molybdenum content and availability in a number of representative areas. In several cases where lime dressings were reported to be still necessary for good yields it was found that the reaction was almost neutral and the lime content high, so that some other factor must be responsible. Soil molybdenum was found to be low, especially the available fraction which appeared to be increased by liming. Field trials with molybdenum have therefore been instituted. Invermay Agricultural Research Station The Invermay Agricultural Research Station is situated one and a half miles from Mosgiel, and the property, which has an area of 1,260 acres, was taken over from the Department of Lands and Survey in July, 1949. The land consists of 220 acres of first-class alluvial flat, 500 acres of second-class undulating clay land, and 540 acres of third-class hilly land still in its native state. The first-class flat land will be used for fertilizer, crop, and pasture trials and for lamb and beef production investigations. A dairy farm to study town-milk supply problems will also be established. Twelve acres of the flat land will be devoted to a horticulture research station where variety, manurial, and spraying trials will be carried out with vegetables and small fruits. The second-class undulating land will be subdivided and worked on a rotation of pasture, cereal, and fodder crops. Investigations will be carried out on pasture and crop production problems on this type of land and on fat-lamb production. Drainage problems will also be investigated. The third-class hill land will be devoted to land reclamation and improvement work. Since the Division took over the property the main work has been to prepare the Station for experimental work. Plans have been prepared for drainage, roading, fencing, shelter planting, and the erection of laboratories, offices, and farm buildings. Winchmore Irrigation Research Station Good progress was made on the development of the Winchmore Research Station, and all buildings necessary for immediate work have been completed, so that the research staff have now laboratory facilities available. On the research area a large number of experiments have been laid down, the main projects being as follow : (a) Pasture Establishment. —On pastures established following varying preliminary treatments, measurements of pasture-production were continued throughout the year. This trial has now been completed and results are being prepared for publication. (b) Sheep-carrying Capacity.—This trial, which is designed to investigate the number of sheep which it is possible to carry entirely on grass, consists of 30 acres of irrigated pasture subdivided into three paddocks. In June 90 ewes were placed on the area and growth so far has been sufficient to maintain them, fatten their lambs, and provide hay for winter feed.

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