BREAD FROM WATER

New Zealand Listener, Volume 18, Issue 446, 9 January 1948, Page 8

BREAD FROM WATER

New Zealander’s Work in Canada’s Wheatlands

three or four inches of rain where Canada’s prairie land has one, not so much of its soil disappears in the wind, but more of its fertility goes out to sea. In Canada the maintenance of fertility is not yet a problem: The prairie farmer’s task there, according to L. B. Thomson, O.BE., B.Sc., a New Zealander who has been directing the soil conservation campaign in Western Canada, is not so much to 9 con New Zealand has

keep fertility in the soil but to keep the soil in the paddock. The surface soil in Canada’s wheatlands, he told us, is often five or six feet deep, and does not lose its. fertility. It does, however, lose its moisture, and the most important part of Mr. Thomson’s work consists in protection of the soil against the prevailing south-westerly winds. Representing the Canadian Department of Agriculture, Mr. Thomson is back in New Zealand after an absence of 27 years. He was born in Blenheim, and worked on.a Marlborough run, before going to Canada as a young man. Some of the first settlers in western Canada, he explained, came from the moist countries of Europe. "So they carried on the farming methods of Europe, and just about ruined themselves.: Fortunately the awakening came before it was too late. We realised that instead of making the climate fit our farming we had to adapt our farming to the climate, and that meant, to begin with, newer methods of tillage." P "Even in the production of wheat?" "Tt’s the production of wheat I’m talking about-cultivating land where the rainfall is 10 to 15 inches. On land

like that the plough has not proved the best implement." "You just disc and harrow?" "We one way disc and don’t harrow. The cloddiert the surface is, the better it resists the wind. But we do more than leave it unharrowed. We cultivate in long narrow strips running north and south across the wind. For every strip we sow we leave another strip lying fallow, and even on the cultivated strip we are careful not to bury the standing stubble. We have discovered that six or eight inches of stubble will knock three or four miles

an hour off the wind velocity, and greatly reduce the loss of soil." "How can you cultivate without burying the stubble?" "By using one-way discs. The soil is turned over, but the — stubble, which has been headed and not cut, remains standing above the ground and breaks up the wind currents." "So that is what stripfarming means?" "Yes, that, along with trash-covers anchored in the soil, is what has saved us." When The Listener met Mr. Thomson, he had just finished a tour of the South Island and was about to start on the North. He had seen a good deal of the farmlands lying between the green flats of the Oreti and the hills of his native Marlborough and, of course, he had_ seen much of Otago. So one of the questions we put to him ran something like this: "You know that Otago is entering its centennial year. You know from

your own past experience, and from your reading, something of its history, and you ‘have now seen it more or less after a century of settlement. What have you to say, speaking as a soil conservation expert, of the state of Otago land at the beginning of the second hundred years?" "Well," he began, "soil conservation is common sense, and there’s plenty of common sense in the South. On the good Otago land, I would say that over the past 50 years they have done an amazing job-particularly on the better cropping lands, and they have developed a type of farm economy that takes account of all the principles of soil conservation. At least, I didn’t see any place on the good land where these principles were being disregarded." "What about erosion?" "I expected to see more water erosion than I did. Wind erosion is our problem, of course, in the western prairie states. There we regard conservation as taking four forms. First there is conservation of the soil; second, conservation of moisture; third, conservation of feed -you haven’t the problems of feeding that we have in winter and in times of drought; then, fourth, there is the conservation of finance which is necessary to implement the others. The Otago

people seem to have been pretty good conservers of finance too. "And when I speak of Otago, I mean Southland as well, of course. The work they have done there in the selection and breeding of sheep has been excellent. I’ve never seen better Romneys anywhere, but then I haven’t seen the North Island sheep yet." Fire in the Tussock In the dry-land country of Otago he found conditions closer in type to those of the Canadian prairie land, but not the same commonsense as he had found in other parts of the province. "In that kind of dry land-the 14inch annual rainfall country-it’s a fallacy to try and apply humid-country practices. It is a separate problem and requires separate study. Moisture is the first consideration, that and the mois-ture-holding capacity of the soil; and the problem is how much of your rainfall you can store up. Wheat, for example, when the plant is at the head stage, uses five times the moisture it requires at other stages of its growth. All farming ‘practices, therefore, must aim to conserve moisture. You must base your policy on the precipitation-evaporation ratio. Every time you harrow or culti- vate you lose moisture by evaporation." "What about burning?" "Burning is a very unwise policy on that type of country; you're destroying something which has taken many years to evolve. I’m told you have large areas completely denuded of vegetation-lI’ve walked over some of it, and we have plenty of land in the same state in Canada. But our policy now is to conserve what was naturally there first. We haven’t

had much success with artificial re-seed-ing. In the dry country of the South Island you have tussock grasses of many species, and in all that tussock-land the old grasses protect the seeds and seedlings from both the hot dry weather and the winds. To conserve that kind of grass, controlled practices in grazing are essential. As for burning, no rancher in western Canada would think of it — there’s a law against burning land, but it’s the kind of law you don’t need to enforce. If a farmer suffers burning, say by the railways, he applies to the Government for a reduction in rent-most of our grazing lands are Crown landsand we know that it takes three years for burned land to come back. But I’ve seen lots of burning in the South Island." "The New Zealand farmer usually gives these excuses for burning. He burns to destroy old, unpalatable grasses, or he barns because he’s afraid his neighbour is going to burn, and so gets in first with firebreaks. But most of them burn only when the ground is wet." Crop Cycles ‘s "Well, we don’t even burn on our crop-lands; we leave the stubble sticking up in what we call a trash-cover, to counteract wind-erosion. And we're putting the straw back into the land at the rate of a ton to the acre. In the past 15 years that has made an enormous difference to the land. We don’t tear into the land any more. But in Otago I thought there was too much of a tendency to apply damp land methods to dry land areas." "Leaving Otago and going back to your Canadian prajries, what does your wheat-farmér do when he’s not growing wheat?" "He’s fallowing his land — he takes one crop from it in two years, or two crops in three. There again it’s a question of moisture conservation. Our whole philosophy of dry-land farming has gone through a complete change. For instance, the capillarity of the soil

that we used to read about in the textbooks doesn’t obtain in dry lands. Moisture goes down all right, but it doesn’t come up. Wheat roots will go down six feet where there’s good subsoil, but if the moisture is not there the crop will fail. If there is no reserve moisture in the subsoil it will take half an inch of rain per day for 10 days to mature a 25-bushel crop. "Are your problems the same as those of Kansas and Oklahoma?" "Yes, but theirs are more intense. I saw one farm there where the soil had drifted 20 feet high against the farm buildings. But they’re handling it successfully now. Adversity has its good effects, and to-day the results of research get a better reception than ever before." "The farmer welcomes the scientist?" "Yes, there is no one to-day readier to apply his findings." "Do you work in with the Americans in soil-conservation?" "Yes, they’re great co-operators. They have more money than we have, but we have been able to help them. Their biggest problem, though, is water erosion in Colorado, Nebraska, and thereabouts. The silting of the main rivers in the U.S. has been tremendous. I saw four inches of rain fall in 20 minutes in Colorado and you wouldn’t believe the erosion it caused unless you saw it. They’ve taken to contour farming, etc., there, and to look at the hills you'd think a beauty specialist had gone over them and marcel-waved them." Exports and Fertility "How long do you think a wheat exporting country can go on exportinghow long can it go on feeding a population which may be four, or fourteen, thousand miles from where the food is grown?" "This question of fertility is one we've been investigating for a long time -we’ve carried out fertilising experiments for 37 years now without getting any material change in the yield. Moisture is the answer. Wheat lands which have been cropped for 60 years are as high to-day in such elements as potash, calcium, and phosphorus as they were in their original state, and we estimate that in the dry lands there is enough fertility to stand hundreds of years of cropping yet. We don’t advocate fertilisers. There is no lack of the elements I’ve mentioned, and putting straw back into the land is building up its nitrogenous content. If we were ever to need fertiliser we have unlimited amountswe export tremendous quantities of superphosphate now. Of course, I have been speaking of the dry-land areas. In the humid-land country — in Eastern Canada-we follow the same practice as you do in New Zealand and use fertiliser. But we do have some trace-element deficiencies in all our lands-we get goitred calves and lambs in our humid areas, for example. But in the dry lands the’ water has 40 times the iodine-content necessary for human health. Help from Christchurch "Insect problems are one of our main worries in the dry lands, and the principal pests are grasshoppers, wire-worms, cut-worms, saw-flies, and so on. Saw-flies, which lay their eggs below the wheat head, used to destroy thousands of acres, but now we’ve got a new strain which resists them. One of its parent strains was a hybrid developed by your Dr. Frankel in Christchurch, and we crossed it with several of our own to get resistance to rust and improved baking quality. Don’t think we haven’t got our problems in the wheatlands-but fertility is not one of them."