S.O.S.

Forest and Bird, Issue 32, 1 April 1934, Page 4

S.O.S.

“SAVE OUR SOIL.”

“Save the surface and you save the lot” was the slogan of a 'very successful advertising campaign of paint manufacturers in the United States of America. That country and many others (including New Zealand) have to be concerned with a much more important “save-the-surface” enterprisethe saving of the surface of farming lands, threatened by the ogre of erosion. This ever-increasing evil of soil-scouring is rapidly telling its tale in New Zealand. From North Auckland to Southland one sees the denuding process taking place on the steeper lands with the consequent flooding and destruction of the lower lands. Mr. H. D. Bennett, in “American Forests,” describes the same destruction as occurring in the Mississippi region in the following terms: — “Estimates indicate that every year three billion tons of soil material are washed out of the fields and pastures of the nation. More than four hundred million tons of suspended solid matter and many more millions of tons of dissolved matter pass out of the mouth of the Mississippi River annually. This comes largely from the farm lands of the Mississippi Basin. The greater part of this water-transported material, picked up from plain, prairie, and mountain slope, consists of super-soil, enough

of it to build 1,250 farms of' 160 acres each, all having a depth twice that of the average upland soil of America. Many have used the expression “as rich as the soil of the Nile” without, knowing that the alluvium of the Mississippi flood plain is still richer. Three billion tons of soil lost every year is an incomprehensible quantity. To haul its equivalent from our fields and dump it into the oceans and valleys would require the simultaneous loading of a fleet of trucks running six thousand abreast, every minute throughout every day and night, year in and year out. If it is possible to visualise such an unending parade of hurrying trucks, then one can develop a fairly clear picture of the prodigious cost of this annual washbill of the fields of America. “When this soil has departed from its place of origin it cannot be hauled back. We can restore land which has been sapped of its plant food by continuous cropping, if the solid soil material still remains in the field; but the soil removed by erosion can not be restored for the simple reason that not merely the plant food is taken, but also the humus, the mineral soil particles and the myriads of beneficial microscopic organisms dwelling within the soil.” New Zealand’s physical features —mountainous country from which many rivers have comparatively swift courses to the ocean —should intensify the people’s fear of erosion. Obviously this country cannot afford to have much of its best soil swept out to sea, where it is a nuisance to Harbour Boards instead of the benefit it would be to farmers if left in its natural place!