Mystery Photo

What are these lines?

After examining this image, write your response in an email message to your teacher or exchange ideas with a friend.

Photos used by permission from the USDA Online Photography Center.

Clue #1

A farmer made these lines for a specific reason. (This is not the landing strip for an alien space ship.)

Clue #2

These lines help to save the soil.

Think you know?

The Answer to the Mystery Photo
These lines, called buffer strips, are actually spaces where the farmer plants grass. The space between these lines where crops are planted are called terraces. On sloping farmland such as this, the grass buffer strips prevent heavy rains from carrying the soil away. This practice is called contour farming.

After learning the answer...

Learn more about "art" you can only see from an airplane.

Why Are Terraces Important?

For thousands of years people have used terraces to improve farming. In some mountainous regions of the world, steep slopes are grooved with terraces. Looking down from the side of a mountain, these terraces carve beautifully formed patterns into the already lush landscape. This stair-step pattern makes it possible for farmers to grow rice on the side of a mountain.

Rice Terraces, Batad, Banaue, The Philippines
Copyright: Photo © Reggie Thomson

In Iowa, gently rolling hills and flat lands allow over 90 percent of the state to be farmed. Iowa's varied and beautiful landscape is shaped by patterns best seen from an airplane. But the practice of contour farming with terraces and buffer strips doesn't just make the landscape beautiful. It also helps save the soil.

A beautiful aerial view of strip cropping, Coon Creek and a watershed in Wisconsin.

When contour farming is practiced, the rows of crops are planted around the side of a sloping hill instead of up and down the hill. The rows of crops actually help to slow the water down. Thus runoff from heavy rains that would otherwise run quickly down the slope, flows gently between the rows to grassy buffer strips. When the water reaches these grassy areas, it will not carry the soil with it because the grass helps hold the soil in place.

Farmers as Artists

Most farmers are not thinking about an art project when they practice contour farming. But just as mountain terraces form beautiful and artistic shapes when seen from a distance, contour farming also creates interesting and artistic patterns.

Grant Wood, one of Iowa's most important artists, saw the Iowa landscape as art. In his famous painting of Stone City Grant Wood placed pasturelands, cornfields, and hay fields on the landscape to form a beautiful design. Of course, early contour farming, such as he portrayed in his art, didn't benefit from today's powerful machinery.

Take a Closer Look

Was Grant Wood thinking about soil conservation when he designed this painting?
Can you find places in this painting where he might have "planted" the rows a different direction?
How about buffer strips?
Should some terraces be added here or there?

My "Conservation Conscious" Painting

Using Stone City as a model, create your own version of the painting. Include terraces and buffer strips. Remember which direction crops should be planted on the side of a hill.

Share your "Conservation Conscious" painting of Stone City with your teacher and classmates.