AN OBJECT LESSON

Evening Post, Volume CXI, Issue 81, 7 April 1931, Page 7

AN OBJECT LESSON

DESOLATED HAURANGI

AND THE BACKBONE RANGE

(By the New Zealand Forestry League.)

The second meeting of the Wild Life Council received a report that in itself justifies the movement that led to the formation of that body—a report oa "The present position of the Vegetation of New Zealand," by Mr. W. E. B. Oliver M.Sc, Director of the Dominion Museum. In space at command we cannot-do justice to Mr. Oliver's paper as a whole, but w^c must draw attention to tho following passage:— "The following introduced herbivorous mammals are found in various forested areas of New Zealand, there often, being several species in the same district: Bod deer, fallow doer, Virginian. deer, moose, wapiti, cattle, pigs, goats, opossums, rock wallabies. The alteration in the forest due to.the depredations of these animals varies very much, according to the number of animals present. Thus in portions of the Fiord National Park and in the Tararua Range, where animals arc- few, tho undergrowth is quite dense and little alteration can be detected. In adjacent forest areas, however, as, for instance, the beech forest at the south end of Lake Manapouri and the mixed podo-carp-beech forest on tho Haurangi Eange, the destruction of the undergrowth is almost complete. In its natural state the- undergrowth, in a New Zealand forest consists of a dense mass of shrubs 6 to 10 feet high with various ferns and herbaceous plants on th» forest floor. The shrubs may consist of many kinds of plants, but usually various species of coprosma will be common, while some Araliaceous plants such as the patete or species of Nothopanax will be found. Such ferns, too, as Asplenium lueiduni and A. rjulbif erum will be abundant. In areas badly affected by herbivorous mammals all this is changed. The undergrowth to a height that deer are able to reach may be completely wiped out. Looking through such a forest one may see quite a distance, arid only the trunks of trees meet the eye. The ground will be almost bare, and damp ground will be the •wallowing places of pigs. Not far from 'Wellington, namely, the Haurangi Bange, such a scene of destruction, can. be seen; on the Tararuas, oa' the other side of the plain, especially; on Monnt Holdsworth, the undergrowth is little touched, and a thick growth of shrubs prevents a view and makes penetration, difficult, while a wealth of ferns clothes the forest floor and the trunks of trees. Nothing could be more convincing of the great destruction, caused by deer than a visit to these two localities. There being little or no regeneration in the deer-infested forest, it follows that its ultimate total destruction is only a. matter of time. Long before this, however, the bush! birds will disappear." One of the first things to note about the report is that it is a definite pronouncement by an. expert concerning the Haurangi forest, a,nd may not be set aside, by the mere say-so of people whose inclinations are to minimise damage without denying it. ' The damaga Mr. Oliver vouches for is the equivalent (given time) of destruction. WHAT BROWSERS, PER ACRE, CATj; FOREST CARRY? Another thing to note is that Mr. Oliver is as ready to testify to no damage (or little damage) as to critical damage. He speaks of portions of the Tararuas where "little alteration! can be detected." He is evidently a fair witness as well as an expert. la fact, lie emphasises these two forests (divided by the Wairarapa Plain) as supplying a contrast and a moral. Tha cause of the difference is "the number of animals present" in each case. . If the crux of the question is the proportion of browsing animals present—the number per square mile of forest—it becomes of immediate importance to know whether deer, goats, cattle, pigs, etc., are on the increase in, the Tararuas, and, if ao, at what data the increase, if unchecked, will lead to a degree of annual damage which, the recuperative power of the Tararua forest is no longer able to make good. It may be that, in the Tararuas generally^ even though "little alteration* may be apparent, the,march of the animal enemies—to a point at which' their increasing toll on the vegetation will be rapidly destructive—niayj be relentlessly proceeding. REPORT ON TABARTTA PESTS : NEEDED. ' Again, there may be parts of tlw» Tararuas, unseen by Mr. Oliver, where not little alteration but much alteration is already evidenced. It has been! said that there is evidence of much, alteration on Marchant. This should be tested. It is known that many, more deer are killed nowadays in the Hutt and Tauherenikau basins than' was formerly the case. A Government report upon the position of the Tararuas as a whole, in relation to browsing animals, is evidently needed. The fact that the two active Departments of the Government have bean' waging their deer war in the South! Island is an indication that certain parts of the South Island are considered worse; btft it is no indication that, the Tararuas are not bad. Bad either in present conditions, or in potential conditions rapidly springing from present ones. Haurangi, that abomination of destn lation, is almost the finished article. The best time to apply the remedy to Hanrangi would nave been when Haurangi was as the Tararuas are to-day. Clearly, then, the best way to protect the Tararuas is not to wait until they; are as Haurangi. At the same time, Haurangi forest is not beyond salvage, and steps to eura it are as necessary as preventive measures on the Tararuas. When a deer-attacked, goat-attacked, cattle-attacked forest reaches a depletion that all may see, remedial measures, though not too late, are belated. What is needed is prevision. Already; the time is over-ripe for an investigation of the Tararuas, to ascertain in what localities the proportion of browsing animals is nearing—or has already; gone beyond—tho point at which th# toll on the vegetation exceeds th< native forest's recuperative power. TARARUA, MOTHER OP WATERS. The Haurangi highlands are a detached physical feature of tho Wairarapa. They throw down some rivers, like the Turanganui, but as a key] to waterfLow they are not comparable in size, and importance with the great backbone range called Tararua. Tho Tararuas are tho backbone oS, the whole southern half of the North' Island. They throw down tho Ruamahunga with its Waingawa and Waiohine tributaries; the Tauherenikau;' the Hutt system; the Waikanae; the Otaki; the Ohau; and some of the waters of the Manawatu. Waters governed by the plant-covering and physical conditions of the Tararuas traverse all the rich low-lying lands down to both coa!sts, including Palliser Bay. These waters can bless or curse millions of pounds worth of farm lands. Can the country have a richer asset than this forested backbone? Can any landowner do otherwise than support al policy of close investigation of the Tararuas and jealous protection of their covering forests? Can he call for better evidence than the photograph on this page?