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Some farmers in USA stop using plow to get better crops






About 5, 000 years after man invented the plow, farmers are learning that they can do better without it.

More than 1, 500 agriculture experts from five mid-Atlantic states met to discuss the problem known as " no-tillage farming", which has been applied on millions of acres, about 2 per cent of cropland in production, in the last half dozen years.

No-tillage, or no-till, as it is usually called, means exactly – do not plow the earth. Its increasing application - the Department of Agriculture says more than half of the United States' cropland will be farmed without plowing in 30 years – marks " one of the truly basic changes in the liistory of the USA's agriculture".

Essentially, the process works like this: after the fall harvest, a winter " cover crop", usually rye, is planted in the field. In the spring the rye is killed with herbicides and the main crop is seeded into the resultant mulch by a special planter. Not a furrow is turned, and the field need not to be entered again until harvest time when the cycle begins anew.

The savings1 in time and money over traditional plowing, which includes numerous tractor trips over the field to turn the earth and control weeds, are great. Field tests comparing no-till with plowing showed no-till required a third to a sixth the amount of fuel to plant the same acreage.

The unplowed soil, aided by the protective mulch layer, retains 50 per cent more soil moisture than a plowed field, and cuts erosion by as much as 90 per cent.

The ability of the no-till method to control erosion even on hilly lands also means it can open millions of acres to productive farming that previously had to be kept fallow2 or in pasture.

Crop yields from no-till farming have proved equal to or slightly better than those achieved by plowing. In one popular variation of the process, a practice known as " double cropping", the time saved by not plowing allows farmers to realize an extra harvest of winter wheat or barley before they plant their main crop. A no-till field, with the seedlings3 is not as aesthetic as the neat furrows of a plowed field.

For all its promise no-till is not the panacea for farmers' worries. Insects that were kept in check4 by deep plowing tend to thrive5 in the unplowed soil and mulch of a no-till field. The selection of wrong insecticides can bring disaster. Likewise, correct herbicides must be used to produce enough mulch to check erosion without suppressing the seedlings. The insecticides and herbicides are broken down rapidly in the soil and are not absorbed by the plants.

Notes and Commentary

1 savings - заощадження

2 fallow – під паром

3 seedling - паросток

4 to keep in check - стримувати

5 thrive –сильно розповсюджуватися

 


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