Expert: Modern Farming Has Helped, Not Hindered Mother Nature

The next time you hear someone claim that conventional agriculture has harmed rather than helped soil fertility and crop quality, don’t believe it, advises one expert.

Two frequent criticisms associated with conventional farming are that its practices have led to serious depletion of vital soil nutrients and that crops grown with nitrogen fertilizer are somehow less healthy than those grown in so-called natural soil.

One agronomist isn’t buying it.

“There is absolutely no evidence of that,” says Dr. Charles Mitchell, an Alabama Cooperative Extension System agronomist and Auburn University professor of agronomy and soils.

Mitchell points to the century worth of data Auburn University researchers have gathered from two of the world’s oldest field studies --- the Old Rotation and the Cullars Rotation, established in 1896 and 1911, respectively --- that have shown quite the opposite is true.

Mitchell says that both of these studies were established in soils that “were pretty well destroyed” --- the result of decades of poor agricultural practices.

“They had eroded away from roughly a century of very poor agricultural practices --- not replacing the nutrients that were washed away or that were taken up by the crops,” Mitchell says.

Modern agricultural techniques applied to both plots within the last century have changed all that. This year, for example, the Old Rotation posted an all-time record yield of cotton. Within the last ten years, record yields of corn, soybeans, and wheat also have been posted on the field.

These yields, Mitchell says, testify to the effectiveness of agricultural practices that have been developed and refined within the past couple of centuries --- practices aimed at adding nutrients to the soil, protecting soil from erosion, and, perhaps most important, adding organic matter.

Another big factor has been crop rotation.

“A disease can build when you’re growing the same crop on the same piece of land year after year,” Mitchell says. “But with rotation, you’re breaking up this monoculture and adding organic matter to the soil.”

Moreover, with rotation, Mitchell and other researchers have demonstrated time and again that they “can produce outstanding crop yields that are every bit as good and healthy as any other crops grown anywhere.”

Some detractors are still not convinced. While conceding that conventional practices have improved yields, they stubbornly maintain that crop quality has suffered.

Again, Mitchell isn’t buying it.

“The nutrients are there in the crops,” he says. “They’re just as healthy for human consumption or for industrial uses as they were centuries ago.”

Recently, spiking fuel costs have sparked a renewed interest in traditional alternatives to commercial fertilizers, such as growing legumes.

Before World War II, for example, farmers typically grew legumes as a source of nitrogen for their summer crops. Then, following World War II, nitrogen became a cheap commodity --- or, as Mitchell describes it, “cheaper to buy it in a bag than grow it on a field.”

Now, in the midst of spiking fuel costs, many farmers have shown renewed interest in legumes and other traditional forms of fertilization.

Mitchell has no problems with this as long as people understand that economic factors, rather than any lingering concerns about the safety of conventional fertilizers, are behind the trend.

“It often doesn’t have to do with what is best but what is most economical,” he says.

Posted by Jim Langcuster at October 12, 2006 04:38 PM | TrackBack