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Linseed.—The scope for improvement in this crop in the immediate future lies mainly in the use of better varieties, and some new introductions are giving promising results in trials. Maize.—Marked yield increases over local varieties have been obtained in trials from several maize hybrids secured from various sources in the United States. The maize hybrid line Pfister 360 from that country has rapidly replaced local varieties in the main maize-growing districts, but experiments have shown that other hybrids will considerably outyield Pfister 360 as well as local varieties in many circumstances. Maize variety trials with such hybrids are therefore being extended as rapidly as possible in order that evidence may be accumulated which will enable the selection of the most suitable varieties. Potatoes. —A considerable number of trials which include most of the common potato varieties are laid down in various districts throughout New Zealand, primarily as demonstrations to departmental officers and farmers, but in addition to give valuable information as to the yield, disease resistance, and general suitability of varieties in the various potato-growing areas. A number of more detailed trials compares lines of the same variety of different origins, but this work is still in the initial stages. A series of trials has been completed where sulphate of ammonia was applied with the seed (together with phosphatic fertilizer) in comparison with its application as a side dressing at various stages of growth of the crop to flowering. Contrary to overseas results the later applications of sulphate of ammonia showed no advantage over application with the seed. Three comprehensive trials in the Apiti-Rangiwahia district investigated the effect on the production of seed tubers of row spacing, the spacing of tubers in the rows, the effect of time of planting, and of size of seed. The trials gave conclusive evidence that the closer the spacing of tubers sown within the rows and the closer the spacing between rows, the higher the yields of seed-size tubers and the lower the yields of table-size tubers. The closest spacings were 24 in. between the rows and 10 in. within the rows. Lamb-fattening Crops.—The value of several varieties of sweet lupins in comparison with different varieties of rape and chou moellier as lamb-fattening crops is being investigated. Sweet yellow lupins have proved very useful in the North Island, especially on the sand country of the Manawatu and in districts where rape is an uncertain crop. However, the strain at present available has been most difficult to harvest for seed and the recent development of a non-shattering strain of sweet yellow lupin is therefore a necessary development if this crop is to be grown widely. (4) Miscellaneous Trials Weed Control. —The rapid commercial development of new forms of chemical weedkiller since the war has been paralleled by a demand for information concerning their relative merits, the weed species against which they are effective, and the best time and method of application of the chemicals. The range of hormone-type weed-killers in particular is increasing and these substances have needed extensive experimental work 'to determine their merits as agricultural chemicals. Experimental work to date has enabled the classification of the majority of plant species of importance to agriculture according to their resistance or susceptibility to most of the weed-killing materials at present commercially available. However, the definition of the conditions under which these substances may be most efficiently used requires much further investigational work. More precise information is also being sought as to the effects of these chemicals in terms of crop and pasture yields.

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