Palouse soil acidity at critical level, local farmers say

Palouse area soil samples show critical pH levels after using nitrogen based fertilizer



Timothy D. Murray, extension plant pathologist professor, says acidic soil can negatively affect nutrients in plants and increase chances of toxicity and even diseases.

HANNAH WELZBACKER, Evergreen reporter

The WSU Extension and The Farmers Network will host a soil acidity workshop on Thursday, Feb. 21, at Banyans on the Ridge at the Pavilion in Pullman. Doors open at 7:45 a.m. and the event goes until 3:45 p.m.

The workshop is comprised of a variety of speakers including scientists from WSU, the University of Idaho and the U.S. Department of Agriculture. Interested parties can register online for a fee of $75. Continental breakfast, buffet lunch, coffee and snacks are included with registration.

Carol McFarland, who does outreach and extension work for The Farmers Network, said this event is an opportunity to share new research and management practices to tackle soil acidity on the Palouse.

“We want to help farmers learn more about soil acidity and also support them in making the next best steps for them as individuals,” McFarland said.

Timothy Murray, WSU professor and extension plant pathologist, is speaking at the event about “The Effect of Soil Acidity on Wheat Diseases.”

Murray said soils in the Palouse have dropped in pH since the 1980s, causing an increase in acidity. Lower numbers on the pH scale mean the soils are more acidic.

Soil has a natural acidity level, however the soils in the Palouse are often worse because of the use of nitrogen-based fertilizer.

Acidic soils can impact nutrient availability, microbial activity, aluminum toxicity and plant diseases, he said.

“Lime is often applied to combat soil acidity,” Murray said. “However, this is an expensive fix and we don’t have access to high quality lime in our region.”

Murray said a study from the University of Idaho found certain crops have a critical pH level in the 5.3-5.7 range. Local Pa-louse soils were found to have a pH level of 4.9 and other samples were worse.

The workshop will feature seven speakers and one interactive session using case studies. Anyone with questions regarding the event can contact Carol McFarland,