October 27, 2014 Debbie Sutherland
How to deal with wet fields has certainly become a topic for the eastern part of the prairies. I have talked to several concerned farmers who I am sure a few years ago swore they would never till again. These are farmers who came through the 90s, worked hard to develop a no-till system that was working perfectly; it made sense for their farm economically and for the long term health of their soil.
No-Till farming practices on the Canadian Prairies have:
• Helped farmers get thought the tough economic times of the 90s.
• Elevated Canadian prairie farms from being in a poverty stricken dust bowl to become among the most respected and efficient producers of grain in the world.
• Improved soil quality by building organic matter back up to levels close to what they were before tillage began.
Now many regions of the central eastern prairies have seen rainfall amounts more than double the long term average. As a result many acres were left unseeded, or worse, flooded after seeding. Attempts to spray and harvest wet areas are leaving ruts in the soil that cannot be left unchecked. There is no doubt getting rid of ruts requires tillage.
Many disc tillage equipment manufacturers have popped up on the prairies ready to convince you that this weather is normal and discing your fields will help solve all your problems. With no research to back up their claims they say the fields will be warmer, drier, less compacted, and have fewer weeds!!
To me, when it was just a few sloughs with tall weeds I preferred to mow them so if the wet area was dry enough to seed through in spring I was at least driving on firm ground not loose mud. But mowing alone doesn’t deal with the ruts and it is limited to small areas. Recently, the practice of planting cover crops has begun to look like an attractive tool in wet regions for the no-till tool box, to enhance the other benefits of the practice, while further protecting the soil and its nutrients.
Ruts are a problem that does require spot tillage but excess moisture is best dealt with by growing plants such as cover crops. I subscribe to the idea of many of my Twitter colleagues, #rootsnotiron. If these wet years continue I think we will find that spreading cover crop seeds in wet unseeded and even wet seeded areas, as some innovative corn growers do in regions with excess moisture. If the cover crop seed is broadcast at the end of June the growing plants will cause more moisture evaporation and give your seeding equipment a firm surface to roll over the next spring. The practice of seeding a cover crop that dies from frost in the fall so you can seed right into that in the spring without spraying or making ruts is becoming popular in wetter areas of Northern Europe as well as pockets in North America.
Using growing plants to get rid of excess moisture is a far better long term practice than tillage for the following reasons:
• Growing plants will bring deep nutrients to the surface
• Plants can draw on water much deeper into the soil than surface evaporation from tillage
• Surface evaporation can leave a toxic salt layer on the soil surface
• Growing plants to use up excess moisture will improve your soil instead of breaking it down and leaving it susceptible to erosion.
• Plants like tillage radish will break up any deep hard layers caused by implements traffic
• Mixing a legume into the cover crop will add nitrogen to your soil
• Plants on the soil surface will carry implements better than till soil in the spring.
There are many good on line resources to research what cover crops might work best for your situation. Visit the following links for ideas, but consult your local agronomist for specifics related to your precise growing conditions.
Most farmers have a “cocktail mix” that works best for their farm. You want something that uses lots of moisture, produces some nitrogen roots fairly deep, dies from frost and stays anchored to the soil and doesn’t wrap around things in the spring when you’re seeding. There are lots of experienced farmers out there who are willing to share their knowledge as always.
I see this tillage fad as a quick short term solution. We need farmers, agronomists, and researchers to work together to find less invasive ways to deal with excess moisture. Growing cover crops is one. We also need seeding equipment that can seed through wet stubble and cover crops while warming up the soil for crops like soybeans. That is a more economic and soil sustainable long term solutions to wet cycles.
The field across the fence seeded with cover crop. The soil is quite dry with good deep roots