Research pioneer led a revolution against summerfallow
April 9, 2007:
After finding solutions to wind erosion on the Prairies, Dr. Donald Rennie goes back and gets the proof.
One of Donald Rennie's earliest memories dates back to the 1930s to his family farm near Gull Lake. When the winds would pick up, he and his brother would place damp cloths on the windows of their family farmhouse in order to keep the black clouds of soil from blowing into the house.
"It's funny the things that stick in your mind," says Rennie, "But seeing that fertile soil blackening the sky and dirtying those towels were what really made me think from a young age that there had to be a solution to keep that earth on the ground where it belongs and where it can do it's job."
From his appointment to the Soil Science department of the University of Saskatchewan in 1952, Dr. Rennie has made a career spreading the soil conservation message. He told the story of how summerfallowing, the practice that helped settle the West and made cropping possible in the early twentieth century, was actually destroying the cropland. He'd follow up with the recommendation to leave the stubble on the ground in order to improve farming for the long term. Eventually, people listened.
Rennie's first soil research began with his PhD thesis, where he studied soil structure in Wisconsin. That lead to more research on soil quality and he says his colleagues quickly realized that the solution to erosion then is the same as it is today – to leave the residue on the land. But he said in those days they didn't have the proof, and nobody listened.
"We tried to send the message that you should leave the field white, not black because you were destroying the soils," he says. "But people would laugh at the trial plots and say they were examples of bad farming. We needed more science to back up our claims. Even some of my colleagues said I was spreading misinformation."
He says that by the early '70s they had the evidence to prove that summerfallow and tillage were the wind erosion culprits. The turning point came for him in 1973 at a meeting of professional agrologists in Saskatoon. "I was the first to give my speech laying out the evidence against conventional farming. After thirty minutes the packed room was totally silent, and then there were cheers. I was able to make my case in a way that they couldn't argue against. We had excellent press coverage and the shift in tillage practices started literally overnight."
Not only did tillage practices change, but there has been a major increase in both fertilizer and herbicide usage. The Prairies went from 20 million acres of summerfallow in the early '70s, to only seven million acres 10 years later.
What lies ahead
Dr. Rennie went on to become Dean of the College of Agriculture for the University of Saskatchewan until his retirement in 1989. He also served for 2 years as Head of the Soils, Irrigation and Crop Production Section of the Joint FAO-IAEA Division in Vienna, Austria. He has received countless accolades including the Order of Canada and was recently inducted into the Canadian Soil Conservation Council's Hall of Fame.
Even almost 20 years after his retirement he remains a champion for soil conservation. These days he believes a lot of the soil on the Prairies is in good shape. It is more granular, has higher organic content and handles water nicely. He sees a growing trend in research on the water cycle.
"We must move quickly to research a new generation of "water efficient" farming technologies so that we, as farmers, can leverage our way into the 21st Century," he says. "The future of Prairie agriculture is bright, not withstanding the doom and gloom forecasts as temperatures warm."