Aug 14, 2017Potato growers do their part for soil health
Soil health is the next frontier in agriculture. While the ag industry has seen leaps in innovation in seed technology, equipment design and precision management strategies, there hasn’t been a concentrated effort to aggregate and measure the beneficial effects of innovative soil management strategies — until now.
Nick Goeser, director of the Soil Health Partnership, says by managing soil’s physical, biological and nutrient aspects, practices to improve soil health can make a significant difference in yield resiliency and enhanced environmental outcomes. Additionally, improved soil health can make good business sense, too.
A main goal of The Soil Health Institute and the Soil Health Partnership is to develop better assessment strategies to evaluate the health of the nation’s soils and the work to measure the health of U.S. soil will be undertaken over the next couple years.
“The Soil Health Partnership is a national leader in the research and communication of the benefits of improved soil health,” Goeser said. “Our goal is to quantify the benefits of practices that support soil health, from an economic as well as environmental standpoint, showing farmers how healthy soil benefits their bottom line.”
The partnership is an innovative example of collaboration between diverse organizations, including commodity groups, commercial agriculture companies, environmental groups and government and academia.
John Keeling, vice president and executive director for the National Potato Council, said the potato industry is in the early stages of understanding soil health from a potato-centric view.
“If you look at most people’s strategy for improving soil health, a lot of times it has to do with not disturbing the soil, but that’s not a technique that’s regularly available for potatoes,” he said. “Now, we do a lot of rotational crops, so we can incorporate that, but potatoes offer a unique and interesting challenge because of the soil disturbing activity.”
Potato growers making a difference
Potato growers have been leading the way to understand how soil management can improve yield and quality for more profitable operations.
“We have seen incredible, coordinated engagement from others, too—universities, agricultural companies, food companies, federal agencies and conservation organizations have joined efforts to learn more about soil health together,” Goeser said.
Keeling notes potato growers are interested in strategies that have to do with enhancing soils to make them a part of pest management practices.
“We think we need to develop methods on what counts for improving soil health in terms of potatoes, and we are fortunate to build a relationship with the Soil Health Institute,” he said. “We’re starting down the road to do that. The greatest gains in sustainability may be in soil health, the ability to make the soil more permeable to water so it absorbs water more efficiently.”
Potato growers have invested in research and subsequently adopted practices to improve many components of soil health. Advanced nutrient application is commonly adopted in potato production today and potato growers lead the way in utilizing soil sample data for nutrient management.
“Many potato farmers will use soil sample information to plan for split applications of fertilizers to ensure nutrients are available when the crop needs them — and not leave excess that could be at risk to loss,” Goeser said. “Petiole sampling and in-store soil sampling are also used to optimize nutrient use efficiency.”
Potato growers also understand how critical water management is to optimal yield and quality. They commonly use the latest technology, such as remote soil moisture monitoring and variable rate irrigation, for enhanced water use efficiency. This improves profitability, production and the environment.
“Management for soil health in potato production also includes disease management for soilborne pathogens,” Goeser said. “Routine soil sampling for diseases and nematodes keeps potato farmers one step ahead of pathogens in the field and allows farmers to use pesticides only when necessary and in the right amount.”
Diverse rotations are also used to break pest cycles across weeds, insects and pathogens in the soil. Potatoes are rotated with many crops depending on the region — and these diverse crops could include snap beans, sweet corn, field corn, onions, or many other crops.
The importance of cover crops
Cover crops, which are crops grown for the protection and enrichment of the soil, are often planted immediately after potato harvest to reduce wind erosion and boost soil biology. Cover crops will hold the soil in place to reduce the chance of it blowing away.
Jim Johnson, soils and crops consultant for the Noble Research Institute, Ardmore, Oklahoma, said cover crops are a tool that’s used to provide multiple ecosystem services to improve soil health.
“It’s important to find cover crop mixes that fit regional production systems and all the best management practices to integrate the cover crops into those systems,” he said.
Keeling agrees cover crops are an important part of the overall effort.
“They are going to have to be very unique and we’re going to have to see new cover crops developed, perhaps, because potatoes are harvested late in the fall in a lot of areas where there’s not a lot of time left,” he said.
Early impact
It’s no secret that healthy soils sustain optimal yields and enhance potato quality. Just as important, if less apparent, is the crucial role soil health can play in protecting water quality and other aspects of good environmental stewardship.
“Potato farmers are continuing to recognize many important agricultural management tools to improve soil health and adapt to changing weather patterns and shifting pest pressures,” Goeser said. “Healthy soil can increase crop yield potential over time—something all farmers would welcome.”
Brendon Rockey, owner of Rockey Farms in San Luis Valley, Colorado, has unique practices as a potato grower managing soil health. He is using a systems approach that has improved soil health and biological activity of his soils and that has helped the yields of his more than 30 varieties of potatoes.
Rockey’s farming system includes the use of green manures, multi-species cover crops and compost balanced with inorganic materials, with his overall goal to eliminate toxic chemicals and to minimize the use of synthetic fertilizers.
“I would say one thing that really makes my operation unique is the use of plant diversity to manage my problems. I am on a two-year rotation, so half of my acres are in potatoes, and the other half is in either a multi species cover crop, or a quinoa crop, which includes a companion crop,” he said. “I don’t have a monoculture anywhere on my farm. Even my greenhouse crop includes flowering companion crops as part of my IPM.”
His cover crop this year was a 16-species mix that was designed for grazing.
“In my potato fields, I plant strips of mixed flowering cover crops to create a habitat for predatory insects like lady beetles, and green lacewing,” he said. “In my potato crop, I plant a companion crop. It includes field peas, chickpeas, chickling vetch, faba beans, and buckwheat. The first four are legumes, so they fix nitrogen for me during the growing season, which helps lower my demand for fertility, and the buckwheat mobilizes phosphorous, and adds even more flowers for supporting beneficial insects.”
According to the USDA, with growers utilizing soil health principles and systems that include no-till, cover cropping and diverse rotations, a greater number of growers are actually increasing their soil’s organic matter and improving microbial activity. As a result, farmers are sequestering more carbon, increasing water infiltration and improving wildlife and pollinator habitat—all while harvesting better profits and often better yields.
In Johnson’s opinion, addressing soil health treats many of the causes of the world’s agricultural problems, not symptoms like soil erosion and increased pest pressure.
“Soil health addresses the root cause of symptoms such as lack of diversity, water infiltration and holding capacity, etc.,” he said. “I think farmers are ready to learn more and do more.”
— Keith Loria, contributing writer
