SOIL EROSION

Nelson Evening Mail, Volume 76, 19 August 1941, Page 6

SOIL EROSION

EFFECT OF LOGGING WORK MISTAKEN IMPRESSION Reference is made by the Director of Forestry iM, \. R. Entrican) in his annual report to one aspect of the soil-erosion movement which, he says, constitutes a serious threat to the success of the general forest policy and the future development of the sawmilling and allied forest industries. “As the more accessible forests are logged and mills move further and further into the hinterland,” he says, “ardent but unobserving ! conservationists clamour more and more for a halt to this movement and a lock-up-keep-out policy of j reservation for the more inaccessible forests. Extremists have even ! advocated the limitation of milling | operations to country below an ' altitude of 11)0(1 feet above sea i level.' j Mr Entrican expresses the opinion that too often the effects of abnormal and seismological disturbances are mistaken for those of milling operations, and that enthusiastic conservationists, j when faced with overturned trees land recently-killed standing timber m | the vicinity of mills. attribute the he says, with effective tire regulations (and control, forests even in loggedover areas have been a rarity for 20 lyears. It really took an expert im- ! mediately after logging to distinguish even at a emarkably short distance the actual logged area from the surj rounding untouched forest. Common j bered that often not more than five |of several hundred were actually |iogged per acre. BENEFICIAL DESIRE CTION | "Of paramount importance.” Mr Entrican continues, public recogniI lion of the fact that by far the bulk of j the virgin forests are completely unproductive in that trees are overmature and that any new growth is j more than otfset by decay, but that the very logging operations and abnormal climatic and seismological disturbances which are of such con cern to the conservations actually create conditions Idvcurable to the re-establishment of ;niew crop and thus restore the forest to some degree of true productivity. Recent outstanding instances are the 1937 gale which uprooted many trees in the southern hall' of the North Island anc. the 1939 saltladen winds which killed so many trees throughout the great part of the North Island. Much of the damage done by these winds had been wrongly attributed to logging operations, and in quite a number of the affected forests a young growth of beech, white pine, etc.. now flourishes where windthrown trees originally exposed the mineral soil and seeded in a new tree crop. TIIE MAJOR OBJECTIVE “Conservation as applied to forestry has been defined as the preservation of forests by wise use, and with counter-erosion and watershed values unimpaired and forests restored to productivity. logging of upland forests under forest service supervision constitutes both a logical and indispenMV.V.V.V.V.V.VVAW.V.W/

| sable element in the national forest i effort. Its real significance lies in the! I lari that the major objective of the j forest policy—that of supplying the I Dominion with the bulk of its timber, j requirements can only be achieved | by bringing every acre of forest land! having available the entire standing | timber resources of the indigenous j j forests, even if this ultimately involves' j regulation of cutting on private and : j other lands. i "It is therefore m a double sensei j that upland stands are referred to as j protection forests, since the objective ; jof their management is the protection . j both of their productivity and of their 1 i counter-erosion and watershed values] |as well, incidentally, as of their re-j creational facilities. Only by the in-j | legrated use of the upland forests for j all purposes may the maximum i I economic and social values, both di-I j reel and indirect, be derived by the' public. Extension of the State forest j | estates to achieve this is a corollary.” , 1..W1) BIKNING Later in his report. dealing with; soil erosion, Mr Entriean says that the forest service continues to advocate a realistic approach to the problem: through Dominion-wide control ot I land-burning operations. “No other; ' l measure." he adds, "can give such ef- 1 ' l'eclive results either as quickly or as j economically. A conservative estimate ; ! of its effectiveness is placed al 80 per cent of the theoretical maximum. So ' aggressive is the New Zealand vegeta-i ! tion that no ground is too barren to I ' ; resist its invasion--that is, if burning | jis controlled. Too often observation !of erosion is limited to pastured slopes J 'heavily scarred or even deeply gullied! j without realising that every forest-clad : | hillside bears scars and gullies, j though many are so healed by the i 'ever-invading vegetation as to defy ! casual detection. Bui whereas repeated ‘ j and uncontrolled burning aggravates ' i and perpetuates the one. controlled 1 use of fire arrests and heals the other, i Even much of the harmful effect at- • ! tributable to overgrazing is a direct' j result of indiscriminate burning and ' ! would therefore be corrected by conj trol of firing operations. Simple as the ' premise is. it provides the most prac- ! ticable and economic method of pre- ; venting accelerated erosion.”