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nearly so marked as in the previous season. Determinations of copper in apple-leaves collected from several orchards, including the experimental areas, showed contents of 10 to 18 p.p.m. for the most part. In certain orchards where copper sprays were used more frequently the figures were much higher. Raspberry " Die-back." —Further field and laboratory work has been carried out to determine the cause of '' die-back " in raspberry-canes. The disorder is common in many gardens in the Nelson district. Additional experimental plots to test the value of borax in the control of " die-back " were established during the winter of 1949, and determinations of boron were made on the soils of representative gardens and on both fruit and leaf samples obtained from the experimental plots and from other gardens in the Nelson district. At Tadmor and Motupiko the experimental plots showed pronounced benefit from borax applications. Plots treated with borax came into leaf earlier than the control plots and were superior in both bud and leaf development. The beneficial effect of the applications was noticeable throughout the whole season, but in certain cases disease or the effect of other deficiencies obscured somewhat the outcome of the experiments. This was particularly so in tests carried out in a garden on granite soil at Orinoco. Borax applications to the bushes gave decided benefit in the early part of the season, but later in the season the effect did not appear to be so noticeable. As the bushes in this garden showed poor growth, it is suspected that other factors besides boron deficiency were operating. Determinations of boron in both soil, fruit, and leaves of raspberry-gardens seriously affected with '' die -back '' at Motupiko and Tadmor gave low figures for this element, confirming the results obtained in the field trials. Watersoluble boron in the soils of affected gardens was usually less than 0-25 p.p.m., while the boron content of leaves from this season's fruiting canes was 20 to 30 p.p.m., compared with 50 to 60 p.p.m. for leaves from healthy gardens. An interesting point emerging from the experiments was the beneficial effect of copper on the leaves at the experimental areas. The results suggest that copper sprays are desirable, not only for the control of diseases but possibly also for the nutrition of raspberries on certain soils. Raspberry Manurial Trials.—Fertilizer experiments have been continued in two gardens in Tadmor Valley. In both cases the value of manures is clearly visible when treated plots are compared with the controls. At one garden the use of additional potash with the standard fertilizer gave increased benefit. Mineral and Nitrogen Status of Apple-leaves from the Fertilizer Trials at the Appleby Research Orchard.—Samples of leaves collected from the Sturmer, Jonathan, and Cox's experimental plots in two different seasons have been analysed. Considerable differences have occurred in the analyses of comparable samples in the two seasons owing to differences in date of sampling, and this makes it desirable to analyse a further set of leaf samples before summarizing the analytical data. The results, however, are in keeping with the fertilizer history of the plots, and show well-marked reductions in phosphorus, potassium, and nitrogen where these elements have been omitted from the treatments—e.g., Sturmer (untreated) gave 043 per cent. P 2 0 5 in the leaves, compared with 0-76 per cent, for the plot receiving superphosphate only. Similarly, the nitrogen contents of leaves were 156 per cent, nitrogen (untreated), compared with 1-92 per cent, for the plot receiving sulphate of ammonia only.

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