WEST COAST SAND DUNES.

Northern Advocate, 31 January 1922, Page 3

WEST COAST SAND DUNES.

WORK OF RECLAMATION".

INTERESTING RESULTS

ACHIEVED,

(Contributed to the "Dominion.")

A visit to the Sand Dune Reclamation Experimental Station (a fenced area of about 2000 acres which is part of a block of 6300 acres of Government land on the «ea coast south of the Rangitikei River) discloses some interesting results of the work done by the State Forest Service. It will be remembered that this work wias begiin somewhat hurriedly last winter to relieve unemployment with those not fitted for heavy manual labour. The first feature that catches the eye is some large dunes, GO to 70 feet high, covering areas up to 10 and 12 acres each, well covered with marram grass, planted during the winter, and now showing a good growth, which should effectually prevent the further movement inland of these huge piles of drift sand, known as "wandering" dunes. Some of these dunes in their progress have encroached upon rich swamp land, and are threatening valuable dairy farms distant some three miles from the sea. Difficulty was experienced in obtaining the largo number of sets necessary for the work, as during the war very little marram grass planting has been done by the lessees, and the best supply of good roots can only be obtained from plants which are not more than three yeans old. However, with the planting done last winter, much has been accomplished towards the provision of a large supply of vigorous roots for future work. In reclaiming coastal dune regions (several thousand acres in New Zealand) attention must first be directed to the development and maintenance on what is known as the "fore" dune in order to cut off further supplies of sand from the sea beach. Herein lies the secret of success in the fixation of coastal sand areas. The first problem then is to reconstruct, and fix the "fore" dune. Along the sea beach, where the prevailing wind sweeping in from the ocean has broken the "fore" dune into hollows, known as "wind channels," through which thousands of tons of sand are transported daily when the westerly wind is blowing (as it was the day the visit w T as mad*?), are to be seen experiments with different types of sand catching fences, structures built with the debris brought down by the rivers. Each different fence is numbered, photographs and notes are taken to demonstrate its effectiveness or otherwise, the idea being to find out which is the best way to collect sand in these "wind" channels, and so build up a more or less even "fore" dune. When this has been accomplished, it is kept in position with the help of marram grass.

On account of the quantity of sand thrown up by the sea, and is carried inland by the wind, a narrow strip parallel to, and just leeward of, the "fore" dune, is required as a dumping ground for this sand, the width depending on the local conditions, and may vary from one to several chains. In France, on the Biscay coast, in the Province of the Landes, it is about ten chains wide. Immediately adjacent to this dumping ground will be another strip of several chains wide entirely taken up with native exotic shrubs and trees capable of growing on sand, and withstanding seaside conditions, to form a permanent protective belt.

The "fore" dune having been formed and fixed, the protective belt of shrubs high enough to take the sting out of tho wind and the sand inside the shelter-belt stabilised with marram, then comes the work which .is the ultimate aim of all these experiments and works, namely, the converting of these sandy waste areas into productive forest, thereby preventing the further encroachment by the sand on valuable agricultural land.

To decide which are most suitable shrubs, etc., for the protective belt, trees most suitable to the conditions, and the best methods of establishing them, is the object of other experiments. Different varieties of trees have been planted, some in the low damj) flats, others on the dry ridges.

It has already been demonstrated, so far as can be seen in the few months since these experiments began, that with few exceptions trees from the Rotorua nurseries do not take kindly to the soil and climatic conditions on the coast. Pseudo-teuga Douglassi, the timber of which is commonly known as

Oregon pine, .is. however, doing very well indeed. If tliis tree will grow on the sand dune country in anything like the way it does at Rotorua, where fine stands may he seen, a very profitable return can be expected. Pinus Ponderosa. another useful timber tree, is one that has done fairly well. One-year-old pinus radiata, generally called insignis. raised on sand country, are doing better than two-year trees from R»torun. A small nursery is being prepared where seeds of shrubs and trees will be tried to test germination and growth in

sand, as the French have found that growng the seed in situ gives better results than transplanting. The locality is one little known, and seldom visited by man, away from roads and railways, and only to be reached on foot or .horseback, but nevertheless, any visitor would find much of interest in a work, the national importance of which is perhaps not quite generally recognised yet. A walk of three miles down the beach to Tangiinoana, w-hich can be reached by motor, and is one mile from the . sea at the Rangitikei Heads, will bring the visitor to the old mouth of the Puki Puki stream, now dry, where the works begin and continue down the coast. The camp is to the south-eaist and about one mile inland. Another way in, is from the Sandon-Foxton road down the first metal road north of the, Oroua Downs, then follow the cart track on foot for about three miles, when the camp will be seen on the right of the track.