Exploring production: SAREC analyzes multiple crop, livestock approaches under one pivotWritten by Saige
Lingle – On July 21 the James C. Hageman Sustainable Agriculture Research and Extension Center (SAREC) hosted over 90 farmers, ranchers and interested community members at its 2011 Field Day for tours of the research projects being conducted on the site.
SAREC project manager Jenna Meeks heads the Economic and Environmental Sustainability of Conventional, Reduced-Input and Organic Approaches on Western Crop-Range-Livestock Farms project, which started in 2009 under the direction of UW Extension Soil Fertility Specialist Jay Norton.
Of the project, Norton said, “We got started here on a 36-acre half-pivot in 2009 with a grant from the USDA National Research Initiative in a program area called Cultural Prosperity for Small and Medium Size Farms.”
Norton said the research is supplemented by grants from the Organic Research Initiative and Extension Initiative.
Meeks described the project, known as the SAREC Ag Systems project, as an integration between crops, livestock and range that utilizes three approaches in two systems.
“The goal is to provide a long-term basis for economic, soil quality and other attributes that will help producers make choices about their operations,” explained Norton.
Meeks added, “Producers have a wide range of things to look at – we’re trying to quantify those things.”
The team described three approaches that are overlaid by two different systems, for a total of six treatments in the project. The approaches are conventional, reduced-input and organic production, while the systems are cash crop and beef-calf.
The 36 acres are organized in four wedges subdivided into six sections. In the outside three rings of each wedge, cash crops grow in one-acre plots, while the inner three rings constitute two-acre grazing plots for the beef-calf system.
In the cash crop systems, crops are planted on a rotational basis and are determined by what producers in the area might plant.
The conventional plots follow a dry beans/corn/sugar beets/corn rotation, while the reduced-input approach incorporates triticale as a ground cover after dry beans. The reduced-input approach also follows conservation tillage practices.
The organic plots follow National Organic Program (NOP) guidelines for organic production and use an alfalfa-oats/alfalfa/corn/beans rotation.
“We bounced the idea of using soybeans around for a while,” said Meeks, “but the organic plots will probably be in dry beans next year.”
Within the one-acre plots, other research projects are being conducted in micro-plots, including the research of PhD students in the UW Department of Renewable Resources.
Renée King, a second-year PhD student under Norton, focuses on organic production and sustainable farming, more specifically carbon and nitrogen cycline and phosphorus in the soil.
“Phosphorus is next to nitrogen in its importance for crops and, in Wyoming soils, phosphorus gets tied up in calcium complexes,” explained King. “It is really important to look at how we can release or increase the ability of phosphorus to solubilize in organic soils.”
King is comparing the abilities of a variety of amendments to make phosphorus in the soils more accessible to plants.
“We have two liquid amendments and two granular amendments, including bone meal, raw phosphates, humate acids and compost tea, that are applied over the first four plots,” said King. “We are looking for synergistic actions of these amendments, as well, so the other four plots are a combination of the four amendments.”
King explained there are a number of potential amendments that can be used in organic production, but gaining access to things like large quantities of manure is sometimes difficult. As a result, her research encompasses the economic feasibility of the amendments as well.
“In the future we’ll do some bench-top trials in the lab and look at ramping up application rates to see if there is an economic advantage to using two or three times the manufacturer’s rate,” said King.
Rajan Ghimire, also a PhD student, is looking at three things in his research: soil quality, microbial activity and trace gas emissions.
Ghimire takes soil samples four times a year and analyzes them for different fractions of organic matter, including available nutrients and long-term implications of the amount of organic matter present. The goal of this project is to look at how different crops, amendments and cropping systems affect the soil organic matter, which directly influences the amount of nitrogen available in the soil.
A related study by Ghimire looks at the microbial diversity of the soil.
“Because nitrogen is the most important nutrient for crop production, we are looking at the amount of nitrogen cycling microorganisms present and what kind of cropping approaches help to grow those microorganisms,” said Ghimire.
Ghimire’s final project involves the environmental implications of the three cropping practices.
“We want to see how different agricultural systems have an affect on gas emissions,” explained Ghimire.
Using a PVC ring buried in the ground with a chamber on top, Ghimire is able to use a syringe to take 60-milliliter gas samples, which are injected into evacuated glass vials and analyzed in the lab. These reading can help to determine the microbial activity of the soils because a higher number of microorganisms will respire more, leading to higher emissions, explained Ghimire.
“We also have 10 gas chambers installed in the dryland operations, five of which are no-till and five are organic transition, and in the irrigated land,” added Meeks. “We have taken samples immediately after tilling to see the immediate effect of tillage.”
The beef-calf system of the SAREC Ag Systems project involves 24 cows and 13 calves.
“They will be on dryland pasture all summer, and we will bring them into the feedlots in late fall to wean the calves,” said Meeks.
Last year the cattle were put on SAREC’s GrowSafe system, so Meeks will be able to compare weight data from last year. While the animals aren’t currently grazing the inner three rings of the half-pivot plot, they are consuming baled forage from the pivot.
“Getting water to each of those grazing plots is a logistical nightmare,” said Meeks.
Regardless, Norton is hopeful that in the final year of the trial they may be able to come up with a strategy to graze the test plots as was originally intended.
The SAREC field day featured three tours for attendees to choose from including dry-land crops, irrigated crops and livestock research and featured projects ranging management of herbicide-resistant kochia, establishment of specialty crops such as fenugreek and the impact of calf weaning date on quality grade.
A summary of projects being conducted at SAREC and extension research centers across the state was consolidated in the “2011 Field Days Bulletin,” which will be available online later this year.