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The quantity cruised during the year —182,066,000 board feet —is the greatest in any twelve months since the Forest Service undertook these duties. Of the total amount involved, 26,512,000 board feet (11,407,000) were cruised by the sample method, and, where possible, the use of this method will be increased. For the approximate estimation of timber stands, 9 (10) reconnaissances were made covering 5,458 acres (14,495) and disclosing estimated stands of 54,641,000 board feet (107,943,000). The appointment of a full-time check appraisal officer has enabled the checking of appraisal work to be carried on throughout New Zealand ; 23 such checks were made, in addition to 14 checks carried out by conservators' staffs. A total of 3,196 plots were measured by the Forest Experiment Station for national forest survey purposes, representing 849,000 acres (300,000), and computations up to the volume-per-acre stage have kept pace with the field work. The Forest Experiment Station has prepared and issued local tree volume tables for insignis pine, Douglas fir, and rimu ; local log volume tables for insignis pine; and a standard tree volume table for tawa (also applicable to secondary hardwood species). Considerable work has been done on testing the accuracy of existing standard rimu volume tables. Work has been commenced on the preparation of an empirical yield table for insignis pine and on the collection of data for normal yield tables for the major exotic species. The standard method of assessment of exotic forest stands has been the subject of field tests, and statistical analyses have been carried out with a view to their improvement. 31. Management Policy. —The annual report of 1946 referred, in the chapter on forest policy, to " the national forestry objective of transferring the emphasis on timber production from the indigenous to the exotic forests." A temporary increase in indigenous-timber production in 1947-48 —an increase that will probably be sustained over a second yearly period —brings sharply into focus the strong advisability of firmly implementing without further delay this policy of husbanding our remaining indigenous timber resources. Therefore, it is proposed to take active measures to this end respecting certain State forests in the North Island in the main. Comparing the last three years, 1946 to 1948, with the three pre-war years, 1937 to 1939, total timber production in the North Island has increased by about one-third. Although indigenous-timber production has diminished from 89 per cent, to 69 per cent, of total production, the actual production in board feet has remained the same. In other words, it is only relatively, and not absolutely, that the exotic timbers are taking more of the load from the indigenous timbers. In the three years immediately preceding the war period, exotic timbers could have borne the full production load in one year out of every ten ; at the present time they can do this in one year out of three. The life of the remaining indigenous resources has thereby been materially lengthened, but the exotic timbers should be taking an even greater share of the load and, inversely, should be enabling the indigenous resources to be reserved to a much greater extent for future cutting. The lower the annual cut of indigenous timbers, the larger will be the remaining resources, and consequently the longer will these resources be available for cutting. The indigenous timbers in question are rimu, miro, matai, totara, and other species comprising the " mixed bush "of the North Island. Kauri cutting has been controlled under forest working plans since the year 1941 and it is anticipated that a small sustained yield of that species will be available in perpetuity. The main reason for reducing the annual production of the podocarp timbers such as rimu, &c., are as follows. Firstly, to ensure that when the national forest survey and investigations into the ecology, silviculture, and management of the mixed rainforest stands have been completed there will still be in existence sufficient State forest

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