March 11, 2014 Pat Beaujot
Maintaining Stubble for Soil Moisture: A Follow up to "Vertical Tillage"
At the end of January a soil moisture map of Canada was published by Les Henry in Grainews, as they are every year, showing the moisture levels in the soil across the country. I always find these publications interesting as Les Henry was a professor of mine at University. The moisture levels on the map are recorded at freeze-up in the autumn, and the map is meant as a resource for farmers to give them an idea of what kinds of conditions they can expect for the following year. The last couple of years we haven’t had to worry too much about this, as soil moisture levels for the most part have been adequate or better (2012-13). If you have a look at the map, which follows at the end of this blog, you will see that for the upcoming season, some areas in South West and Central AB as well as North West Saskatchewan, are looking at dry, or in some cases very dry conditions.
Normally, we would be very worried about this. We used to watch these soil maps pretty closely. History has shown that if soil moisture levels are low in the fall, then spring seeding will be difficult as getting good germination becomes significantly more challenging. If we don’t get adequate rains in the summer months, it will be hard to get good crops. After such a bumper crop year, it might seem unimaginable to be back in this situation so quickly, yet here we are.
In conversation with some dealers, I have been hearing that vertical tillage equipment has been selling very well in several areas of Saskatchewan such as the Battlefords and Lloydminster, areas which are known for dry years. If they are practicing more and more tillage, and moisture levels are low, and they don’t get some good spring rain, the farmers in the area could be in trouble.
Part of the reason I think we have forgotten to heed the warnings of something like a soil moisture map anymore is because of no-till. So much of Western Canada has adopted the practice, and seen it working for them for so long, that drought has become less of a concern. For farmers who left stubble standing and haven’t tilled, their fields will be trapping snow and preventing moisture loss in spring. Germination won’t be a problem for these savvy growers because there will be a bit of reserve there. It is so critical to get that crop off to a good start. There is still potential for a drought as you can’t control the weather, but at least they will get that good start. However, those who have been tempted by the lures of vertical tillage will have lost the moisture that was there, and will be losing moisture when the sun is shining and the wind is blowing in March.
Maybe a wake-up call like this is what is needed every once in a while to remind us of why we went to the trouble of switching to no-till in the first place, and why it is so important to leave stubble untouched in the fall. The most I’d like to see is heavy harrowing or harrowing in the fall if the stubble looks too hard to seed through. We did have a great crop last year, so there will have been a lot of stubble to deal with this year managing that stubble is so important. I just think that there are better ways to deal with it than tillage.
It will be interesting to see how this plays out this spring. I’d like to get up into these projected dry areas in a month or so with my moisture probe to see the difference between some of these vertically tilled fields and the no-till ones. At home in Langbank we’ve been labelled in the blue area, which is labelled “wet”, so we may not see a significant difference here, but I will be checking here as well. Comment on the conditions you are seeing in your area, your thoughts on vertical tillage, and how you maintain your no-till farming operation from year to year.