Building soil health starts with the basics
Casper – Farmers and ranchers can’t afford to lose soil anymore than they can afford to lose livestock or crops, according to Caitlin Youngquist.
At a soil health workshop on Nov. 28 during the 2017 Wyoming Natural Resources Rendezvous hosted by Wyoming Stock Growers Association and Wyoming Association of Conservation Districts, multiple presenters discussed the foundation, evaluation and bottom line for soil health.
Caitlin Youngquist, University of Wyoming agriculture and horticulture Extension educator, presented an introduction to soil health and why farmers and ranchers should take care of their soil.
Youngquist told attendees there are a few ways to define soil. The first definition is that soil is a living system with plants, insects and microorganisms.
Soil can also be defined as really old rocks that serve as inherent characteristics in current soil.
“Inherent characteristics can only be changed over thousands and millions of years,” noted Youngquist, adding dynamic characteristics can be changed within a season or several years.
“As land managers, producers work within the constraints of inherent characteristics to improve dynamic characteristics to the best of their ability,” she stated.
The process of turning rocks into soil takes millions of years, noted Youngquist because the rocks weather over time and break down into smaller particles. Eventually, the rock particles become a living system with plants, insects and microorganisms.
“Based on the best estimates, the process takes 500 to 1,000 years or more for one inch of topsoil to develop,” stated Youngquist, “Topsoil is very valuable, precious and fragile.”
“Producers should consider how long it takes to recover any little bit of topsoil that might blow away,” she added.
Youngquist described inherent characteristics of the soil as the factors producers cannot change and need to be aware of. Inherent characteristics include soil texture and soil type.
“Soil texture is the percentage of sand, silt and clay in soil and dictates the strengths and weaknesses of any soil,” she said.
The type of soil is also important, noted Youngquist, who explained there are 12 soil orders across the globe and over 15,000 individual soil types around the world.
“Depending on the size of a ranch or farm, producers could have a few dozen soil types to manage,” she stated. “Having a better understanding of the type of soils producers are working with will help them manage land better, in terms of understanding the strengths and weaknesses of their soils.”
She also explained that soil formation isn’t random and takes millions of years based on several factors.
Factors include where the soil is on the landscape, like a hilltop or river valley, the climate and parent material.
“Cold, dry or hot climates affect soil type, and parent material, like glacial soil or volcanic ash, all influence the soil types,” Youngquist said. “All of these factors impact the strengths and weaknesses of the soils producers deal with.”
“Understanding the soil, the strengths and weaknesses of the soil and how to manage the soil are really important in terms of being a good soil manager,” stated Youngquist.
Soil health can be thought of as the ability of the soil to function and be resilient, stated Youngquist.
“Whether it’s livestock, humans or land health, they need to have a high capacity to function,” she added. “If producers have healthy land, it needs to be able to adapt and self-manage in the face of challenges, or be resilient.”
Producers should determine if their soils are resilient to compaction, disease and erosion, noted Youngquist.
According to Youngquist, plant roots and water are largely responsible for creating healthy, productive and profitable soils.
“In grassland soils, there is four to five times more biomass both below than above ground, and up to half of the biomass is recycled every year,” she said.
Recycled biomass includes roots that die back or slough off and turn into carbon organic material in the soil, explained Youngquist.
She stated biomass recycling is why high grass prairies have deep and fertile soil because all the grass and grass roots have been recycled for thousands of years.
The plant roots take carbon dioxide out of the air and put it into the soil where it is useful and productive, also known as carbon sequestration, she added.
“The process supports soil microbial life, which in turn helps the plants and soil develop,” noted Youngquist.
To increase soil health, producers need to increase soil organic matter and soil carbon.
“Carbon is the system driver and comes from the plant roots into the soil,” Youngquist explained. “To increase soil organic matter and soil health, producers need to get carbon in the soil and keep it there.”
Roots are a big part of increasing organic matter and soil health, especially on rangeland. When looking at increasing soil health on hay fields or cropland, Youngquist suggested adding compost or manure.
“Once producers get the carbon in the soil they need to keep it there, which means minimizing soil carbon loss, like tillage,” she stated.
“Getting the carbon in the soil and keeping it there is key because the carbon feeds the microbes,” added Youngquist. “So, get carbon in the soil, feed the system and let it work the way it was designed to work.”
During a soil health workshop on Nov. 28 in Casper, Caitlin Youngquist, University of Wyoming Extension educator for agriculture and horticulture, stated there are three important characteristics of soil.
“When the chemical, biological and physical characteristics of soil are all considered, that’s when soil health is achieved,” she stated.
Scientists have been practicing soil chemistry for a long time, according to Youngquist, which includes measuring pH levels, acidity, salts, nitrogen, phosphorus, potassium, macronutrients, micronutrients and carbon in the soil.
Biological characteristics of soil are assessed using crop condition, disease pressure and the amount and type of microorganisms.
“Physical characteristics are things like like erosion, compaction, infiltration and soil structure,” noted Youngquist. “Scientists are really good at the chemical and physical side of soil and need to learn a lot more about the biological side.”
“If producers are missing one of the three factors, soil health decreases, which is not profitable,” she concluded.
This is the first part in a four-part series detailing soil health and managing soil. Look for part two in the Jan. 20 edition of the Roundup.
Heather Loraas is assistant editor of the Wyoming Livestock Roundup and can be reached at firstname.lastname@example.org.