THE OTAGO DAILY TIMES TUESDAY, AUGUST 21, 1934. NEW ZEALAND FORESTS

Otago Daily Times, Issue 22346, 21 August 1934, Page 8

THE OTAGO DAILY TIMES TUESDAY, AUGUST 21, 1934. NEW ZEALAND FORESTS

New Zealand has received credit for doing more than any other dominion in recent years to extend her forest area. The view has been authoritatively advanced that a progressive policy of afforestation and forest improvement must in her case prove a profitable national investment. In the latest annual report of the State Forest Service the general forest policy is set forth as " the perpetuation of the indigenous forests and the provision of a supplementary exotic forest capital which, by rapid growth, will eke out the supplies of indigenous timber and bridge the gap between the exhaustion of the over-mature indigenous forests which otherwise would occur, and their conversion into healthy productive forests." It is added that, with the establishment of the exotic plantations now approaching completion, it will be possible to give proper attention to the silyicultural treatment, of the indigenous forests. This touches an important aspect of forest service operations. On the subject of indigenous forest management this report is highly instructive. It characterises as entirely erroneous the prevalent idea that, to preserve the existing native forests to posterity, it is sufficient to fence them against stock and to protect them from fire. That is not enough, for it seems that the native forests are not otherwise capable of looking after themselves. The Director of Forestry is explicit in the statement that the composition of the forest gradually changes, one type of forest growth succeeding another. Generally, he says, the valuable timber species are replaced by weed species. Further, we are informed that of the remaining virgin forests over 80 per cent, consists of over-mature stands in which there is no net growth, new growth being offset by decay, etc. While :t cannot be welcome in any. case, such information would be the more unpleasant if no other conclusion were rendered possible than that the fine indigenous timber trees are doomed by a natural process against which there is no remedy. The position is apparently not quite so unfortunate as that, however, though it brings, or should bring, into particular prominence the great significance attaching to conservation as the most important feature of the national forest policy. The conversion of the 80 per cent, of over-mature forests into healthy growing stands of indigenous species, producing timber to the maximum capacity of the forest soil, can be achieved, it is indicated, at the cost of silvicultural management extending over a long period, probably 150 years. It is at least well that no doubts should exist as to the nature of the task ahead. An illuminating reference to the tendency which has to be combated is contained in the following statement: — Of all the indigenous softwoods amenable to silvicultural treatment, kauri is outstanding, and the results of investigations have been most promising. In many of the remaining kauri forests the percentage of over-mature timber lias already risen to as high as 50 per cent, (by volume), emphasising the urgent need of marketing such timber before it further deteriorates, and of managing the forests to encourage the growth of the immature trees and to secure re-establishment with young growth. By no other means can the kauri be preserved to posterity. If further neglected the over-mature trees will continue to decay and die. and the healthy ones will follow suit much quicker than otherwise, until ultimately the whole of the kauri growth will be replaced by a climax succession of taraire, rewarewa, etc., which already are commencing to take command.

The question whether silviculture can achieve the salvation that is desired is answered hy the affirmation that as soon as the demand for timber returns to normal it is the intention to bring the whole of the national kauri forests under management plans "which will ensure (heir perpetuation for all time." This seems to he a confident pronouncement, and the hope can only be expressed in the meantime that in the conservation of our indigenous forests it will be fully justified in years to come. The impression is conveyed, none the less, that study and experience will figure largely in the tale. Nothing could be more deplorable than the thought of the possibility of the ulti-

mate decay of such an asset as the country's great national arboretum, so vividly described by the GovernorGeneral on Arbor Day, and all the attendant consequences, one of which would presumably be the gradual disappearance of many of our beautiful native birds. The alternative apparently consists in patient and enlightened silvicultural effort. But this must be allied with recognition by the community of the need of commonplace safeguards. " Too much emphasis cannot be placed," urges the Director of Forestry, ''upon the fact that the greatest natural enemies to the standing bush and forest regenei-atien are fire and browsing animals, and it may be regarded as a sine qua non that unless these two menaces are rigidly suppressed all efforts to conserve and regenerate our forests will prove futile."