You see a patient in a hospital bed on an intravenous drip. All nutrients and energy are fed to the patient through the tubes. The patient doesn’t get up, doesn’t have to move, doesn’t have to buy groceries or fix dinner, much less sit down at a table to fork the food in. Sweet life, right? No effort, all gain? Except that somehow, we know this isn’t ideal – not even close.
Yet that’s exactly what we ask soil to do when we spoon feed it all the nutrients it needs to grow a crop. In that scenario, we artificially supply everything the plant might need, through dry or wet applications, to get the best crop possible. Still, somehow, we instinctively know something’s not quite right. The problem: We’re making our soil lazy.
At the Mini-Cassia Soil Conservation District soils conference this spring, soil ecologist Dr. Christine Jones made the patient-soil analogy and said, “We’re putting down seed dressing, pre-plant and post-plant and all kinds of phosphorus and nitrogen, instead of making the patient work itself. It has legs. It knows how to find those things, how to function. Let it function.”
How sick is your soil?
The first step to knowing how to “treat” soil, is knowing how sick it is. So how do you know if soil is healthy and on artificial “life support?” Linda Schott, soil specialist with the University of Idaho, offers a brief questionnaire to help with assessment:
- Does it blow away? Is there a dust cloud behind the planter or disc?
- Does it flow away? How much sediment are you losing in runoff?
- Does it allow water to soak in quickly or does it puddle?
- Does it crust?
- Are there areas where plants die or grow poorly?
Answering affirmatively to any of these areas indicates soil problems.
Cover crops are part of the solution
How, then, do we get the soil off life support? One part of the solution is to plant cover crops.
Luke and Sara Adams have been promoting soil health on their farm near Rupert, Idaho, using cover crops since 2012. “On our farm it’s a known input,” Luke says. “There’s no question of should or shouldn’t; it’s a question of how many acres we can put in.”
Luke and Sara admit the jump into choosing a cover crop mix can be daunting because of the variety of covers available, and they offer some advice to growers just getting started. “First,” Sara says, “Address a specific problem.” Some of those problems could include:
- Nematodes – These require trap and biofumigant crops like oilseed radish (not Daikon) and “trapping mustards” or white mustard varieties.
- Erosion – These require higher-carbon mixes that would include more cereals and clovers, species that are more winter hardy and carry more sustainable residue into spring and early summer.
- Water infiltration – This requires diverse root-structure mixes that might include radish, mustard or crops that will terminate over winter. But if you’re limited on water, stay away from mustards.
- Fertility – To address fertility, this mix would include nitrogen-fixing and nutrient-mining crops such as legumes for nitrogen and forbs for phosphate.
- Financial – If the goal is to create more revenue, then a marketable double-crop (hay or grazing) mix might include oats, grasses or sudangrass.
“Knowing your goal ensures you select the appropriate components for your mix,” Luke says. But other factors come into play, such as: What’s your target planting window? What are your planting options (drill or broadcast)? What’s your termination plan? What will your following crop be (you’d hate to create unnecessary competition)? And what times of the year are you busiest (what does your management style support)? How will you handle the residue (graze, flail, shred)?
Doug Huettig farms with his brother Steven near Hazelton, Idaho, and has 10 years of experience with cover crops in rotation with sugarbeets, corn, edible beans and malt barley. He uses a no-till drill (for custom hire) and prepares custom cover-crop mixes. His goal is to provide not only ground cover but grazing for livestock.
After barley harvest, Heuttig will no-till plant a cover crop (into small grains, following harvest) and then start grazing the volunteer winter barley and cover crop by mid-September. Through the winter, stockers and the cow-calf herd are fed hay as needed. Weaning happens in March, and by early April, previous fields of spring barley seeded with cereal rye can be regrazed. By early to mid-May, the cattle can be moved to range or perennial pastures. Cows calve in May and June. This setup provides one month per acre, per cow-calf pair.
Huettig grazes grass-finished stocker cattle. Last spring, he had so much early growth he ended up baling some of it. Then he planted warm-season annual grasses for summer grazing. This experiment taught him: The BMR sudangrass didn’t do well, as it was planted too late in the summer, and there weren’t enough heat units to bring it along very far, and if he did it again he would plant half in the spring and then later no-till in the warm-season annual grasses, with millet and grazing corn for grazing over the winter.
The high cost of winter cow feed several years ago was what drove Rulon Spears to cover crops on Spear and Hinckley Farms near Raft River. He uses cover crops on about 800 acres of their 1,720-acre farm. His daughter Hannah says, “When we started, cow feed was 200 dollars per ton, and we were feeding 2 tons per head at 450 cows, plus the cost and time to put the feed out, so it was costing about 420 dollars per head to feed for seven months. Now we spend less money on feed and the cows and calves gain more.”
One experiment involved grazing grain corn. “If we had cut it for silage, it would have made about 40,000 dollars, but because of what the calves gained and what the cattle market improved, we made about 80,000 dollars,” she said. Because it was grain corn and not grazing corn, it required moving the cows often and not letting them graze continuously in the corn, but they gained 2.3 pounds per day.
Using cover crops, Jones said, can help jump start your soil health. While it’s not an immediate “fix,” it can combat several problems, and it at least allows your soil the ability to function as it was intended to do.
