THE OLD AND THE NEW.

Forest and Bird, Issue 49, 1 August 1938, Page 12

THE OLD AND THE NEW.

A NEW ZEALAND STORY WRIT IN SILT

“Not the silt we used to have,” says the East Coast farmer when the floods descend upon him, and bury his high-value soil under many feet of hinterland spoil. No, it is not the old silt; it is spoil in every sense of the word. The valley soil is lost, and a new and inferior medium for grass-growing is presented to the farmer, who straight way turns for help to the Government and the mortgagee. Nothing any of them can do is of much avail now. The remedy would have been to do nothing years ago. Doing nothing is not usually a virtue, but it is the highest virtue if compared with what the farmer and the sawmiller have done to the high inferior country, the surface of which man was incapable of turning into a farm, but which yet was within the compass of his powers of destruction. Mr. H. Guthrie-Smith, himself an East Coast farmer, who knows well his Hawkes Bay lowlands and highlands and watercourses, has explained the difference between the old silt and the new silt. In “Sorrows and Joys of a New Zealand Naturalist” he describes the havoc on the hills, and adds: “On the alluvial flats it takes a different form. They too are threatened by the ultimate effects of grazing of sheep and cattle on uplands that never should have been open to the axe and plough. “In olden days, before the country was stocked, before its primeval vegetation was destroyed, floods indeed occurred as now. River banks were, as nowadays, bitten out and gouged, but these inferior soils of the bleaker inland were filtered throughout every mile of the river’s run; the coarser soil was deposited by blockage of dense riverside jungle and undergrowth. In those days millions of detaining leaves and blades stemmed the flood, each acting as breakwater, each hoarding its own tapering tail of debris. Thus only the finest silt, the most minutely comminuted vegetable matter, reached the flats. The mouths of rivers were then, moreover, in great degree canalised;

the current was confined by the dense growth fostered by conditions of damp luxuriance and oceanic warmth. “Now bad unfiltered soil is superimposed on good. Moreover, with the trampling and browsing of stock, especially of cattle, these guardian thickets were broken down and destroyed; the untrammeled river broke bounds; long-deposited layers of silt and vegetable mould were directly engulfed by the sea. In place of flat terraces on either side of a deep, smooth, straight river, we have a main stream torn into shallow channels, its mouth altering at every fresh.” What Mr. Guthrie Smith wrote in Hawkes Bay in 1936 has just received a further demonstration in Hawkes Bay in 1938. The process of making New Zealand “little better than a home for white men” had been going on for a hundred years, but the damage has intensified in the last two generations because the occupation of all the grassable lowland has pushed would-be farmers into ungrassable highlands, where the grass product of their labour disappears in a few years. The “constant stirring by sheep’s feet of shingle on the screes,” the “nibbling of the specialised plant species that bind the stony slides,” and “the perpetual fires of modern methods of alpine sheepfarming” in due course ruin the highcountry farmer and also ruin the lowland farm. It is all part of a chain of cause and effect that is still active. Agricultural Department experts have confirmed the deteriorating effect of the silt that piles up on valley lands, and have thus confirmed prophecy. But from a remedy the country is as far off as ever.