For farmers on the Canadian prairies, water is precious as gold.
With an average precipitation of 300 mm (12 inches) water resources are tight on a normal year. But weather is rarely normal and recent years at Prairie Son Acres have been on the dry side of the scale, leaving us searching for ways to get more moisture in the ground and keep it there.
Prairie farmers have a long history of water conservation. Given our naturally dry conditions and limited water resources, irrigation is rarely used. And dating back to the 1930s (i.e. the Dirty Thirties), Canadian farmers began to adopt simple but effective water management practices. Crop rotations were introduced and summer fallowing land was discouraged, tall stubble was left on the field in fall to collect snow, bushes and shrub rows were planted to prevent wind and water erosion. As modern technology created new techniques, like direct seeding and min/zero tillage, prairie farmers were quick to pick them up. These combined efforts have done much to help conserve our limited moisture and has undoubtedly prevented a repeat of the dust storms as experienced in the 1930s.
But water is precious and we always want more.
Towards this effort, we at Prairie Son Acres have turned to regenerative agriculture — in fact water infiltration and retention was one of the key features that originally attracted us to the regenerative farming movement in the first place.
As much of the land we farm has slightly sandy top soil, erosion and nutrient leaching are key concerns. There is also an ubiquitous hardpan that begins between 6-9 inches below the surface. Approximately 5% of our acres have a saline condition – poorly drained soils with groundwater pushing salts up to the surface.
With these soil conditions in mind, we decided on four key goals that are specifically focused on improving our water management:
- Breaking up hardpan soils and creating/improving soil aggregation
- Improving water infiltration and maximizing water holding capacity
- Increasing carbon in the soil to trap water and prevent erosion
- Optimizing water usage to produce as many bushels per inch of moisture as possible
After a bit of time examining our regenerative farming playbook, paging through various water management tactics, we realized that the solution to all these problems was regenerative farming’s universal answer for almost all things: more carbon!
More roots, more critters and more crap.
Roots to break up the hardpan and attract critters both big and small (e.g. from microbes to earthworms). Critters to feed the roots and create soil aggregates. And crap (i.e. cow manure) to feed the critters and provide a cheap and easy source of carbon. Now, this is a grossly oversimplified explanation of the complex relationships between these three components, but it does serve to highlight the basic interconnectedness for those in our coffee room who are more interested in the Cliffsnotes than the hard science (for those who are interested in reading more about it, check out our other articles: Five Principles of Soil Restoration: Revitalizing the Carbon Cycle and Soil as an Ecosystem).
Of course, it helps to be more specific, so here is what he have actually done thus far:
- Introduced a variety of tap roots, including large tubers, into our cover crop mixes. We focused on root diversity and having a living root in our very limited growing season for as long as possible on both freeze up and thaw. Tap roots (canola, alfalfa, clover, turnips) will penetrate hard pan and will improve water infiltration. Fibrous rooted crops (wheat, barley, oats,) have large root mass (up to 6’ deep in the ground) and add lots of carbon to the soil. Added benefit of efficient water use and increased crop competition.
- Included crops that have a high C:N ratio (e.g. flax) in regular crop rotations. A high C:N ratio has the long term benefit of improving SOM by adding lots of carbon to soil. Crops like peas have a low C:N ratio and therefore have a net removal of carbon to balance the N in the residue.
- Used a growth manipulator. This is a plant growth regulator that decreases the stalk length of wheat. It reduces the energy required for shoot growth and therefore increases available nutrients and water for seed production.
- Added humic acid to our granular fertilizer mixture. It’s an easy carbon source that will improve fertilizer use efficiency, make nutrients more accessible that are in the soil and improve water holding capacity.
- Introduced grazing animals. Cattle provide lots of organic matter, dense with nutrients and a supercharged carbon cycling method that would take the average plant years to accomplish. Animals are by far the most efficient way to take a green plant and recycle its carbon (and other nutrients).
- Practice minimum and zero till seeding. We do both, using drills and a disc seeder respectively. While zero till is preferable in that the ground is less disturbed and therefore retains more moisture, minimum till seed does have its place on northern farms. Notably minimum tillage exposes some soil that aids ground thaw and can lead to quicker seed germination. With our short growing season, it’s a balancing act and the best method is dependent entirely on ground conditions when it’s time to seed.
So far the results of our efforts have been hard to quantify. Observational data suggest some progress but with only three years of reliable hard data collected we have only just established a baseline with which to judge our future progress.
We know that regenerative farming is a long game, soils don’t change drastically over the course of a single year. However, we know we are headed in the right direction as every decision we make is made with the goal of building carbon in the soil and conserving water. With this process well under way, we are optimistic that when our current bout of dry conditions break, our soils will be ready to capture every drop of rain.
So informative!
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