H.—34,

Entomological Investigations.—During the year Miss G. E. Wall finished her investigations on the insect pests of phormium. This work had reached such a stage that it was possible to make suggestions for experiments on the field control of the three major pests —the leaf-eating caterpillars (Melanchra steropastis and Xantherhoe praefectata) and the scale Leucaspis stricta. These suggestions embrace : (1) The cultivation of soil and keeping grass away from the base of phormium plants at the time M. steropastis and X. praefectata pupate. These 'times are September to November, and February and March. (2) The removal of dead leaves in which the larvae of M. steropastis and some X. praefectata take shelter during the day. These leaves also provide a place of pupation for M. steropastis and should be removed when green ones are cut for milling. (3) Spraying the grass immediately around the base of phormium-plants is recommended as an alternative method of attacking M. steropastis during the grass-eating stage. (4) The use of a flame-thrower to destroy the grass around the plant. This practice can hardly be recommended owing to fire danger. (5) In the case of L. stricta, spraying with red-oil spray immediately it appears is the best method of control. A full account of all the insect work is being prepared for publication. Future Investigational Work.—lt is considered that ample varieties of phormium have been collected on the Batchelar and Easton Areas. Any further breeding-work will therefore practically cease, as it is not likely to yield plants better than those already selected. Future investigational work will mainly take the form of experiments connected with the formation and maintenance of plantations. These will include further manurial trials, cultivation trials, cutting trials, &c. Life-history and ecological studies of the various varieties will also continue. MECHANICAL INVESTIGATIONS. Mr. L. Ledges. Investigations relating to the mechanical processing of phormium have been concentrated on the improvement of a flax-stripper which will permit complete stripping of the phorinium-leaf. The first tail-stripping machine was tested out in Foxton on the premises of Messrs. A. Ross, Rough, and Co., Ltd., at the beginning of 1938. The first four months' tests showed that the initial design could be improved upon principally in the direction of delivering the stripped fibre to the washing-apparatus. A new design incorporating a number of improvements was evolved, and a second stripper, known as the " Sutton Tail Stripper," was built. This machine was completed in November, 1938, and subsequent tests have shown that, while not yet perfect, it is a distinct advance on previous strippers. This stripper has been in continuous operation for six months. The experimental work involved the testing of the first tail stripper ; the drawing of plans and supervision of construction of the second machine, together with its subsequent testing ; and, finally, the preparation of full working drawings incorporating further modifications for future tail strippers. A portion of Messrs. Ross, Rough's mill has been leased to the Flax Plan Industrial Committee as a site for the development of further machinery for the treatment of phormium fibre. Work on the construction of an improved washing-machine has been commenced. CHEMICAL INVESTIGATIONS. At the Dominion Laboratory chemical investigations on phormium have followed two main lines : (1) The examination of various processes for the decortication of phormium fibre; (2) the chemical examination of several varieties of phormium, in an attempt to correlate varietal difference with differences in the quality of the fibre, as measured by chemical methods. This work is described in fuller detail in the Dominion Laboratory section (p. 94). TIMBER-PROTECTION RESEARCH. Timber-protection Research Committee—Mr. V. Lough, State Advances Corporation (Chairman) ;* Mr. R. L. Andrew, Assistant Dominion Analyst; Mr. F. J. A. Brogan, Assistant Secretary, Department of Scientific and Industrial Research ; Mr. F. R. Callaghan, Chief Executive Officer, Plant Research Bureau; Dr. G. 11. Cunningham, Director, Plant Diseases Division, Plant Research Bureau; Mr. H. C. Cayford, Housing Construction Department; Mr. N. A. Marris, Dominion Laboratory ; Dr. D. Miller, Director, Entomology Division, Plant Research Bureau; Mr. A. F. Clark, State Advances Corporation (Secretary). At the request of the State Advances Corporation a Timber-protection Research Committee was set up by the Council of Scientific and Industrial Research in June, 1938, to direct and co-ordinate investigations relating to the preservation of timber from the attacks of insects and fungi. Field surveys by officers of the State Advances Corporation have revealed that the incidence of insect and fungus attack on wooden buildings in New Zealand is sufficiently serious to warrant a full investigation of the problem in order to obtain the fundamental scientific knowledge upon which to base effective control measures. At present there is a lack of knowledge concerning the life-history and habits of the insects and fungi attacking timber in New Zealand and the effect of various types of wood-preservatives on New Zealand timbers and on the insect themselves. It was for the purpose of providing an effective research organization to investigate problems of such importance as these that the Timber-protection Committee was established. The discovery, as a result of a recent survey by officers of the State Advances Corporation and the Department of Scientific and Industrial Research, that the white ant is causing serious damage to buildings in the Auckland district has made it necessary for the Committee to give immediate attention to this as a new and urgent problem.

* Deceased.

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