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and the adoption of a simplified method during the past year has. resulted in the same field parties doubling the area assessed. One-fourth of the total area of State exotic forest has now been assessed. Assessments are comparable with the national forest survey, but are on a more intensive scale and carried out over smaller unit areas, the forest compartment, rather than the whole forest, being the unit. For both investigations aerial maps are of very great assistance if not indispensable, and it is unfortunate that the assessment of certain forests must be postponed owing to aerial photographs being as yet unavailable. 7. Exotic Silviculture.—lt is again stressed, as in annual reports of recent years, that the thinning of the very large areas requiring this improvement work cannot be delayed indefinitely. Neglect of thinning involves loss of increment, danger of disease and fire, loss of timber in the trees which die instead of being removed and utilized, and also dangerous and difficult conditions for logging workmen, when the stand is ultimately clear-felled, owing to the presence of numerous dead standing trees (up to 450 per acre in some instances). During the war years the average annual area thinned was 800 acres, and during the two post-war years this has only very slightly increased to 815 acres. The reason for this is, of course, that additional workers required for thinning projects are not offering. It is of interest to record that the wartime clearfelling rate of 170 acres annually has increased in the past two years to 270 acres. Almost the whole of the clear-felled areas had received no thinning treatment, but the one compartment which had been properly thinned at the appropriate period yielded 50 per cent, more timber per acre than the unthinned compartment. The extent of the loss of increment owing to neglect of thinning is obvious, while the quality of timber also suffers. 8. Land Acquisition.—ln view of the small numbers of forest workers offering for employment, the recent slow progress in acquirement of sub-marginal land areas for consolidation of existing State forests, for extension of young kauri areas, or for •establishment of new exotic forests in timberless regions will not in itself retard the postwar forest expansion programme. The policy of ensuring that land suitable for farming is not acquired for forestry was Closely adhered to. One large area was interdepartmentally inspected, and several further areas are awaiting inspection.' This policy embraces not only open lands for planting but provisional State forests under consideration for permanent forest dedication. 9. Water and Soil Conservation and Forest-fire Prevention. —During the year the closest collaboration has been maintained between the Soil Conservation and Rivers Control Council and the State Forest Service, and a member of the State Forest Service was appointed to the-post of Forestry Liaison Officer. The appointment of this officer marks the increasing emphasis which is being placed by the State on soil-conservation measures of which a significant part is the acquisition and management of large areas of sub-marginal land as " protection forest " by the State Forest Service and the continued protection and management of State forests with due regard to soil conservation. The State Forest Service controls several millions of acres of protection forests, and reference to past annual reports—more especially those of about fifteen years ago—will show to the inquiring reader that the Dominion forest policy has for many years been abreast of that of older countries, which have long regarded the preservation and management of "protection forests" as one of the most significant contributions of a Forest Service to the well-being of the community. It is intended that the Forestry Liaison Officer will keep the Soil Conservation Council constantly in touch with forest policy in so far as it affects, soil conservation, and that the joint, inspection of land for acquisition as State forest by all interested Departments may be considerably facilitated. The bodies interested in such inspections

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