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additional senior research officers. Some references to the year's work are given under " Forest Management " and " Silviculture " (paragraphs 28, 29, 30, 32, 49, and 50, and paragraphs 80 and 81 of this chapter). 78. Forest Research. —Interpretation of the ecological observations undertaken as a part of the national forest survey is beginning to throw a clearer light on the research problem' involved in the management of indigenous forests. It has never been thought that the ecology of New Zealand forests (the study of the dependence of their component plant communities upon one another and upon their environment) was simple, and in particular the difficulties in managing podocarp stands have always been realized ; the indications now are that the problems are more complex than had been expected, even for pure beech forests, and that the forest survey, rather than solving these problems,, is merely for the first time stating them clearly. The course of action, however, is equally clear. The primary survey is concerned with mapping and describing the many different forest associations and with indicating the ecological status of each. From a forest management point of view, two major ecological categories can be recognized: (1) those that reproduce themselves, and (2) those that do not. The latter category is characterized by light and infrequent seed crops ; paucity of natural regeneration ; complete absence or, at best, poor representation of sapling and pole stages ; stagnant and overmature trees ; and a general down-grading of the association (following destruction of its own micro-climate). Forests in this category cannot be considered truly adjusted to the present climate and" soil. In theextreme cases forest management is impossible, since any interference will result in reversion to shrub, heath, or tussock. In all other cases management directed towards perpetuation of the original association is equally impossible, since the successional trends are towards hardwood or, on occasions, minor softwood forests. Management should be possible, although the composition of the second crop will inevitably be changed. The other major category (No. 1) shows less stagnation, a more normal distribution of age and size classes, and signs of definite regenerative vigour. All the evidence suggests that such forests are well adjusted to their climate and soil and are in fact true climatic or true edaphic climaxes. Management in this category is not only possible and desirable, but in some areas it is already taking place. The steps to be taken are obvious. Firstly, the primary survey with its attendant interpretative work must be completed. Secondly, the forests most amenable to successful management (mainly in category (1) ) must be segregated, and their reservation as permanent State forest assured. Thirdly, a programme of detailed and intensive research must be commenced in forests of both categories. Such a programme should lead to the evolution of silvicultural systems which will follow the natural and inevitable trends of forest succession and which will not, instead, attempt to " fly in the face of Nature." Fourthly, and to some extent concurrently, the silvicultural systems evolved will have to be translated into practical possibilities by large-scale management experiments designed to find out the most suitable and economical harvesting techniques. The research programme will demand staff with intensive training in forest ecology and of the very highest calibre. The problems are so intricate that only by attacking them with teams of research workers investigating all the biological, practical, and economical considerations involved can any success be hoped for. With only flimsy historical records of the behaviour of these forests, and even then only over the past few decades, and with no literature on long-term investigations into similar forests overseas, many years of carefully designed experimental and observational work will be required. The programme, in fact, must be essentially long-term in nature and must, as pure research, look to not fifty but two or even five hundred years ahead. The growth-rate of indigenous species is so slow and, for some associations, the intermediate or " nurse " stages are likely to be so prolonged that the results will not be evident for many generations to come. This fact, however, must not act as a deterrent. The

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