From an airplane I've noticed farmlands plowed in circles. Why do they do that, instead of straight rows?

Answer 1

If they are exact circles, they were likely plowed by a machine and designed for irrigation. The pump is placed in the center and rotates around a pivot.

If you refer to curved patterns that is called "contour plowing" and is done to prevent erosion by plowing along the contour of the land.

Answer 2

There's a very long "arm" that sits on a tire thet is fixed at the center of those circles. The arm sprays water and rotates around the center. The circles are where the irrigation takes place.

Answer 3

In the 20ties they ploughed in straight lines ,and the wind comes along and picks up speed ,millions of tons of top soil where picked up and blown away causing the famous dust storms leaving the ground barren of toip soil

today they have learned something and plough in circles to avoid this accumalation of speed ,and the removal of soil by wind erosian
but they still havent got it right
no land should be naked under the sun ,that causes it to dry out and makes it easy for the wind to pick up the dust .

thes are better ways like No Till farming

this means not using a tractor and planting in mulch

the tractor is used inicially to shape the land and to make it receptive to water harvesting.
but after that the top layer of soil is left in peace so that microorganisms can get on with building soil

Answer 4

United has it right. The circular plots are for the use of a rotating irrigation system. This prevents the need for open flood irrigation, and all of the environmental concerns and cost of flood irrigation.

Answer 5

They have very large sprinklers that water in a circle .