“Has shown great improvement, but needs to do better.” That’s David Rourke’s report card on progress to improve soil health on the Prairies.
“We will need to look at minimizing soil disturbance, more plant diversity and keeping something growing on our land from snow to snow,” the Minto-area producer told the Manitoba Sustainable Energy Association (ManSEA) conference in Brandon Feb. 10.
Rourke said the improvement in soil health will reduce dependence on chemical applications and improve fertility and water retention.
As well as farming, Rourke operates AgQuest, a company that provides research in product and fertilizer efficiency, variety development and environmental trials.
Rourke’s presentation addressed climate change, agriculture’s contribution to the national carbon footprint and the need to prevent the 2 degree rise in global temperatures that has been predicted by climate scientists.
“Climate change is a serious global problem and it is getting worse. We are in a country where we have the opportunity to try and salvage what we can or we can continue as status quo and we will run into major problems,” Rourke said.
He said that over his 36 years in farming, he has seen the agriculture industry come a long way in reducing its environmental impact, and that he believes it can continue to be at the forefront of environmental stewardship.
“We have reduced tillage, implemented continuous cropping, diverse rotations; we have made energy-efficiency gains in tractors, trucks and combines, we use the four Rs in fertilizer practice to make those as efficient as we can, we have superior genetics, and a lot of our farms use precision placement,” Rourke said.
But despite the improvements there are still salinity problems, a decline in organic matter and many water-management problems.
“Regardless of the global climate change, I think we have issues we aren’t addressing. We are not storing enough water where it falls and that is causing erosion issues, flooding, and road wipeouts.”
Zero till not the answer
Rourke did his master’s degree on zero-till practices, but said after years of farming he has seen that zero till doesn’t hold all of the answers.
“We all scratch our heads because we thought that organic matter would increase as soon as we started zero tilling and problem solved,” said Rourke. “But, I believe this isn’t happening as quickly as we thought because we are not using enough of the growing season compared to what Mother Nature would have.”
Along with zero-till practices, Rourke says there is a need to have complete soil cover at all times of the year to promote microbial bacteria growth.
“In our system we are probably only using about 80 to 90 days of actual active growth and that doesn’t feed the soil microbes as long as it needs to. We are cutting the food supply off by about half,” he said.
Cover crops, companion crops, longer-season crops, and perennial crops, are the things that are what is going to make the difference in terms of soil organic matter, he suggested.
“Any time you don’t have plant growth, the soil goes backwards. We have a huge challenge and a huge opportunity to figure out how to use that entire growing season, from snow to snow.”
Rourke said pasturing livestock is an ideal way to increase soil’s organic matter because you can grow a cover crop for the full season, then graze until spring, never leaving the ground uncovered.
“We as producers have a choice right now. We can either go on this route that is not going to be good for our great-great-grandchildren, or we can make some changes,” Rourke said.
“As we move down this road, I think it offers us a new focus on soil health and I think that we need to keep our minds open and use every tool that we can. We will innovate with the best and I think there is opportunity to turn this around.”