‘A Quiet Crisis’: The Rise Of Acidic Soil In Washington

Aug 19, 2015

By Sylvia Kantor

Gary Wegner first noticed the problem in 1991, when a field on his family’s farm west of Spokane produced one-fourth the usual amount of wheat. Lab tests revealed a surprising result: the soil had become acidic.

Winter wheat affected by acidic soil.

Wheat farmers are now seeing this problem across the inland Pacific Northwest. The culprit, as far as anyone can tell, is the abundant use of synthetic nitrogen to increase crop yields, a practice that has otherwise revolutionized production over the past half century.

“We’re riding the edge of a crisis,” says Paul Carter, an agronomist and the director of Washington State University Extension in Columbia County. “We can pretty well nail it down to the addition of nitrogen to our soils for crops. In 1940 or 1950, nitrogen was applied at five pounds per acre. Now, in some areas, we’re up to 100 or more pounds per acre.”

Source: wsu.edu

Video: Root Exudates, Soil Biology, and How Plants Recruit Microbes | Field Talk Friday

Field Talk Friday | Dr. John Murphy | Root Exudates, Soil Biology, and How Plants Recruit Microbes

Most of us spend our time managing what we can see above ground—plant height, leaf color, stand counts, and yield potential. But the deeper you dig into agronomy, the more you realize that some of the most important processes driving crop performance are happening just millimeters below the surface.

In this episode of Field Talk Friday, Dr. John Murphy continues the soil biology series by diving into one of the most fascinating topics in modern agronomy: root exudates and the role they play in shaping the microbial world around plant roots.

Roots are not passive structures simply pulling nutrients out of the soil. They are active participants in the underground ecosystem. Plants constantly release compounds into the soil—sugars, amino acids, organic acids, and other molecules—that act as both energy sources and signals for soil microbes.