- Jim Chamberlin
Soil Health, Part Three
Jim Chamberlin, Happy Dancing Turtle’s Conservation Technician, also operates a 109-acre diversified farm and forestry operation near Deerwood, MN, with his wife, Audra. His knowledge about and enthusiasm for what we can do for soil and what soil can do for us will fuel this four-part series of blog posts.
In the previous blog posts, we introduced the first three principles of soil health. Soil health is defined as the “ability of soil to function as a living ecosystem.” In this post, learn more about the fourth and fifth principles, keeping in mind the context of all five soil health principles:
Armor the Soil
Keep Living Roots in the Soil
Manage for Context
Diversity creates resilience. Financial advisors will tell you the best bet for long term investment is a diversified portfolio. Farm diversity has been lost in the wake of efficiency, but our soils need a diversity of plants to be resilient and healthy.
Different species of plants emit different types of plant exudate (or plant snot as mentioned in Soil Health, Part Two) out of their roots. These different types of exudate, as the base of the food chain, support different species of organisms making the soil food web more diverse.
This leads to a more resilient soil ecosystem and makes nutrients more available to plants. Some plants, particularly woody plants like trees and shrubs, change the chemical makeup of the root exudate as the plant matures, the makeup of organisms in the soil food web changing with it. Greater diversity above ground equals greater diversity below ground, and a more resilient overall.
Extending crop rotations is one of the best ways to increase farm diversity. Going to a four year or longer rotation not only helps promote the diversity of organisms in the soil, it also helps break up pest and disease cycles and can reduce nutrient deficiencies caused by growing the same crops year after year. Incorporating small grains is one way to extend rotations. Growing small grains opens up opportunities to incorporate cover crops for more of the growing season, and if utilized as forage, can supplement other livestock feed.
Seeding acreage to perennial pasture for two or more years is a great way to extend crop rotations. Adaptive grazing on these pastures can fuel biological soil fertility and will reduce fertilizer needs when rotated back into row crops. More on this under the next soil health principle, Integrate Livestock.
Agroforestry practices, the integration of woody plants into cropping systems, take diversity to the next level. These practices can be designed to yield a harvest and create additional revenue streams for the farm. There will be more on agroforestry in part four of this series.
Rotation: One More Tool for Gardens
In your garden many of the same tools apply. Rotating crops, companion planting, cover crops, and integrating perennial plants into your garden all help to diversify your landscape and build soil health.
Most pasture walks I go to that highlight adaptive grazing involve a paddock change, where livestock are moved from one area of a pasture to a fresh one that has had adequate rest, regrown tall and lush. The vigor and excitement the animals have for moving to new ground emanates from the animals to the people watching.
They move like migrating wildebeest on the Serengeti (on a much smaller scale), as onlookers pull out cell phones to shoot videos and pictures. We’ve been rotationally grazing livestock for a couple of decades at Island Lake Farm and I still get joy out of watching animals move to a new piece of ground.
In this video clip, Isaac Tappenden and Kent Solberg talk about tip grazing for body condition going into winter. Healthy soils, healthy animals.
Building soil health requires mimicking nature. The most fertile soils on our planet, the prairies and savannas, evolved with large herds of migratory herbivores. Predators kept them tightly packed and they moved constantly, maybe not returning to the same ground for a year or more.
These herbivores ate the best parts of the plants, and trampled the rest, leaving behind a biological treasure trove of cellulose, lignin, urine, manure, saliva, hair, and disturbance. All this fueled soil biology, from dung beetles rolling up balls of manure and bringing them underground for their young, to the fungi and microscopic nematodes, protozoa, and bacteria, an elaborate food web evolved. This is how six-foot deep topsoil was built.
During a recent Pasture Walk at the George Heller Farm near Wadena, Kent Solberg examined the soil and explained the positive influence animals have on the soil, just by their presence: "As soon as a cow walks into a paddock, what happens? That cow is walking biology. The cow's shedding biology and it excites the biology in the ground/all around," said Solberg who is the Senior Technical Advisor for the Sustainable Farming Association of Minnesota.
We now have technology, like electric high tensile and polywire fencing, ATV’s, and adaptable watering systems that can be used to mimic the way these herds moved, and rebuild our soil. Virtual fencing is an upcoming technology with incredible promise, allowing livestock managers to move animals to a new paddock with their laptop or cellphone.
Farmers and ranchers are adopting adaptive grazing because it saves time and money vs hauling manure. They find that by building the health of the soil they can run more livestock on the same amount of land. They are integrating animals into cropping systems to graze on cover crops, fueling natural soil fertility, reducing or eliminating the need for synthetic fertilizers that leach into our lakes, rivers and groundwater.
Public land managers are teaming up with farmers to use livestock to control invasive species such as buckthorn and garlic mustard, and restore native habitats such as oak savannas. Livestock are an integral tool, and like all tools must be used properly to be effective.
Chickens Are Good Grazers for Gardeners
Poultry are a good fit for small scale gardeners. Using “chicken tractors” to move through a garden plot will break up pest cycles and add fertility, and depending on how long they are left in one spot you can have them work the soil bare or use mulch to build a deep mulch bed.
We had a neighbor who would buy two feeder pigs from us every other year and turn them into his 30’ by 50’ garden at the end of the season. His garden would get fertilized, they would eat weeds like quack grass, and he would fill his freezer.
If livestock isn’t a fit for you, adding composted manure is an easy and effective way to add animal impact to your garden. Whenever livestock is incorporated into crops, specifically those eaten raw, care should be taken to avoid contamination. Using well composted manure, or separating fresh manure applications from harvest by 120 days is recommended.
In the next blog post, learn the last soil health principle, Manage for Context . In the meantime, when traveling through farm country, look for landscape diversity and ways it could be improved. Observe pasture for residual forage, is there at least 4” of plant growth to support root growth? Explore ways you can diversify your yard or garden. Build a compost pile, or find a good source of composted manure.
Science has yet to replicate what comes out of the back of a cow. Let’s use what nature gives us to build soil and grow our food.
Coming up in Part Four, the final in the Soil Health Principles series, the importance of managing for context, and the series summary on how we can take agricultural conservation to the next level.