H.—34.

(2) Seaweed Utilization. The possibilities of seaweed utilization in New Zealand are being explored, and a full report is in the press. This gives details of the uses to which seaweeds have been put, including the preparation of fertilizers, potassium chloride, iodine, stock food, human food, agar-agar, alginic acid, &c. Methods of harvesting, processing, and cultivation are discussed. The useful New Zealand species are reviewed, and the extent to which they are or can be made use of. Work is in progress on a survey of their distribution and availability. (3) Tussock-grassland Investigations. A detailed study of the taxonomy of the indigenous grasses has been nearly completed and will be made use of in the field work planned for the coming year. Studies were made on the effect of spelling, with especial consideration to the regeneration of the better grasses. Erosional studies were continued, and a paper has been published on certain effects resulting from interference with the plant cover. Evidence was given before the Sheep-farming Industry Commission, and reports submitted concerning the botanical aspects of changes in the tussock-grassland and on the relative palatability of the component species. The Director attended the conference of runholders held at Lake Tekapo in April, and discussed various problems with members. Assistance was given to the regrassing work at Pisa Flats conducted by the Department of Agriculture, and further experimental work is planned for the coming year. (4) Weed Investigations. Intensive laboratory and field work on hard-fern control has been continued, and a report is in preparation. Some work has also been done on St. John's wort and tutsan, with especial reference to seed germination and spread. Work on Californian thistle is being planned. Experiments with the scythe method of sodium chlorate treatment are proposed. The botanical work on ragwort has been completed, and a bulletin is in the press. Bulletins on noxious weeds and poisonous plants are in preparation. Preliminary ecological work on gorse and broom has been commenced. (5) Medicinal Plants. Work has proceeded on various medicinal plants, both from local and from overseas sources. Supplies of foxglove leaf have been collected locally, dried, and stored. Preliminary tests indicate that the leaf contains glucosides beyond the minimum required by the British Pharmacopoeia. A small supply of Digitalis lanata seed has been procured from Kew for trial. Supplies of locallv grown leaf of Datura stramonium, have been tested, and the leal satisfied the standard requirements. Roots of a native gentian are under test for glucoside content. Seeds or bulbs of the major medicinal plants have been procured from abroad. Germination has proved very poor, but it is expected to raise enough plants to secure seed supplies for further work. (6) Vernalization. Preliminary trials with rye-grass and white and red clover justified field experiments. Further work, with investigations on the effect of temperature and light on growth factors, was held over to a more opportune time. A pot trial with Algerian oats indicated significant responses. The results are being statistically analysed. A small trial with cocksfoot is under way, and suggests that a, more rapid establishment, with better tillering, is likely. (7) Phormium. During the year work on the Batchelar Area, Massey College, was put on a maintenance basis, as there is every possibility that in the near future this area will be combined with the Easton Area on the Moutoa Estate. The plantation on the Easton Area has been maintained and some 10 acres broken in for nursery work. On this area about 1 acre of seed-beds were sown and approximately 100,000 seedlings of selected varieties lined out. This work was done in anticipation of the acquisition of the Moutoa Estate by the Government and the laying-out of it as a phormium area. Attention has been directed to the need of fine fibres for string and fabrics. A considerable amount of crossing was therefore done with a fine-fibred type of Phormium tenax and Phormium colensoi, which has fine and silky fibre. A quantity of P. colensoi leaf was cut from the cliffs of Wellington and the fibre from it is awaiting a large-scale string test. Also, for the purpose of obtaining fibre for string, a quantity of leaf was cut from two-year seedlings at the Batchelar area. A vegetation survey of the Moutoa Estate, recently acquired by the Government, has been completed. Important ecological results derived from this should assist in the laying-out and maintenance of the estate. (8) Miscellaneous. An examination has been made of the seed content of moa-crops, and further work will be done as opportunity offers. An examination of the histology of rye-grass leaves at various stages of growth, and under various conditions, is in progress, to ascertain its bearing on problems of facial eczema in sheep. A map of the primitive vegetation of New Zealand is in preparation for the Centennial Atlas, and papers on the taxonomy of indigenous plants and general ecology are in preparation.

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