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timber, but care has to be taken to ensure not only that the " film " is continuous and adequate, but also that the materials used are not likely to prejudice the health of those handling the timber or to affect subsequent painting. There are still a few dippingplants in operation, but with the increasing use of pressure-treating plants the need to used dipped timber will tend to disappear. . Pressure-impregnation methods of treatment are available in Christchurch and in most parts of the North Island, the plants being centrally located to give a wide coverage. It is expected that other plants will be erected in the near future. These plants are treating a very considerable volume of the sap grades of native timbers, such as rimu and matai, and also of native hardwoods such as tawa, which were formerly of little commercial value owing to their susceptibility to insect attack. In addition, considerable volumes of exotic timbers, mainly Pinus radiata, are being treated. With the adoption of preservative pretreatment by pressure methods the Board can anticipate the use of lower-grade timbers to a greater extent, and, although insect and fungus attack is not the only consideration in the acceptance of these classes of timber, the general adoption of pressure preservation will overcome most of the difficulties in their use. With the permanence of the timber reasonably ensured, long-term lending can be entertained with confidence, and the interests of the Corporation's clients protected. Termites Act, 1940 The Corporation has continued in its administrative and technical functions under the Termites Act, 1940, which provides for the detection and control of various species of non-indigenous termites that have become established in New Zealand. By arrangement with the State Forest Service, responsibility for inspection of imported hardwoods arriving from overseas has been accepted by that Department, which also arranges for isolation and treatment of any infected timbers. The inspection of existing buildings is undertaken by the local body concerned, and the Corporation treats any infected properties found. In due course certificates may be issued by the Corporation certifying that the property concerned is free from termite-infestation. Both the inspection work .and the treatment require expert knowledge, and staffing difficulties have prevented the work proceeding as speedily as the Board would like. It is unlikely that the infestations will ever be completely eliminated in all localities, but adequate control will ensure the protection of much valuable property. During the year the number of properties inspected and of infestations recorded up to the 31st March, 1949, is as follows:

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Local Body. Properties Inspected, Including Re-inspections: Total as at 31st March, 1949. Properties in Which Infestations Found: • Total as at 31st March, 1949. Auckland City Council Mew Plymouth City Council .. Onehunga Borough Council Mount Albert Borough Council One Tree Hill Borough Council Mount Eden Borough Council Mount Roskill Road Board 18,519 1,446 1,231 569 1,040 337 699 340 23 111 4 2 2 23 23,841 505