TAUPO SOILS AND SAWDUST

Taupo Times, Volume I, Issue 17, 7 May 1952, Page 5

TAUPO SOILS AND SAWDUST

Questions Answered

(By

"Flora")

[Taupo gardeners with problems on their minds are invitecf to send these to this column for advice.] Two questions have neen asked by "A Taupo Gardener." (1) Is it possible to get an analysis of a typical Taupo soil; as it would be of great heip in deeiding what types of fertiliser to be used. It is not the policy of the Department of Agriculture to undertake the testing of ga'rde'n soiis owing to the shortage of staff; and the large volume of farm soils that have to be given attention. But I think the foilowing advice will give you an idea of what our soil lacks; enabling you to treat it accordingly. If the analysis of many pumice soils collected from the Taupo district are any criterion, and I think they are, then it is highiy probable that the chief requirement of your garden soil are phosphate (superphosphate, basic slag, or bone dust) and organic matter, such as would be provided by digging in green crops (blue lupin, oats, clovei', etc). This latter requirement is most important and no mineral fertiliser can adequately take its place. I suggest that you try the following mixture of fertiliser: 4 parts ,superphosphate; 3 parts blood and bone; 1 part muriate of potash. Used at the rate of 2 to 3 ounces per square yard, and lightly raked into surface soil. (2) What is the best way of growing plants in deep sawdust filled gullies ? I surmise that your gullies are filled with sawdust collected straight from the saw-bench. This is not a happy medium for the growing of plants. You might as well mince up a few sacks and expect a good crop of carrots. Perhaps this is somewhat exagerated; but ,till the sawdust has, at least partially decomposed there is little food value in it. Unless an activator — chemical or annimal manure — has been mixed with the sawdust it seems to take ages for decomposition to take place, I have had a small heap of sawdust for about eighteen months. I dug the centre a while ago, and oniy in places did it show any signs of rotting; and then mostly round pieces of stringy bark; which have had particles of dirt adhering to them. As far as I can see, your best plan will be to cart in soil; and cover the sawdust to at least a depth of 12 inches. Even then, it is doubtful if you could grow anything but surface rooting plants for a year or so. After rather condemning fr'esh sawdust in large quantities, I would like to tell of two instances of how little soil is required for actual groWth. Have you ever visited the golddredgings on the West Coast of the South Island ? It was perhaps 20 years ago that I was there. A depressing sight; hundreds of acres of freshly washed boulders cast up in ridges, six to eight feet high. Now I believe, pine plantations cover these areas. Year by year a little dust was blown up; small plants grew and died, each adding his mite; but in the end enough for the doughty pine. The other example comes from a little further aheld. There are two elms growing in Fifth Avenue, New York. Huge pillows, reaching up three or four stories; and thicker in the trunk than a man. These trees are remarkable, because they are the only vegetation on that stone-canyon-shaded boulevarde. The most unusual thing about them, however, is that they are not planted in soil at ail, their roots set no doubt in a tangle of wires and cables and conduits are nourished wholly by chemicals. I hope a wonderful garden grows on your sawdust heap, and so confound the critics. Next week 1 will continue listing shrubs suitable for Taupo conditions; and that can be planted during the next three or four months.