USDA Report-Agricultural Conservation on Working Lands-Trends From 2004 to Present

The USDA’s Office of the Chief Economist (OCE) recently released a report title, “Agricultural Conservation on Working Lands: Trends From 2004 to Present.”  A fact sheet that accompanied the report explained that, “The first step toward increasing adoption of conservation practices is to establish a baseline of current adoption rates;” and added that the report, “uses survey data to track U.S. adoption of selected agricultural conservation practices that both reduce GHG [green house gas] emissions and provide additional environmental benefits.”  Today’s update includes brief excerpts and highlights from both the report and fact sheet.

Contributors to the OCE report included: Marci Baranski, Helena Caswell, Roger Claassen, Charlotte Cherry, Kirsten Jaglo, Alex Lataille, Sharon Pailler, Diana Pape, Anne Riddle, Drew Stilson, and Kate Zook.

Background

The authors explained that, “Tracking every conservation practice is beyond the scope of this report; as a result, the scope was narrowed to track a subset of working-lands conservation practices producing a common benefit: reduced GHG emissions or increased carbon sequestration. Specifically, we included practices that were targeted as part of USDA’s Building Blocks for Climate- Smart Agriculture and Forestry initiative and narrowed those to practices for which survey data were available. Such practices include reduced tillage (mulch tillage and no tillage), nitrogen management, use of cover crops, use of precision agriculture technologies, and use of anaerobic digesters for manure, which generate GHG benefits by reducing emissions of nitrous oxide, methane, carbon dioxide, and/or increasing carbon sequestration.”

The report stated that, “Application of nitrogen fertilizers to soils is the largest source of GHG emissions in agriculture. In 2015, it accounted for approximately 75 percent of N2O emissions and 3.8 percent of total emissions in the United States.”

“Corn had the highest nitrogen per acre application rate and the highest percentage of applied acres of the three crops studied,” the report said.  (Soybeans and wheat were the other crops reviewed in the report).

With respect to corn acres in the U.S., the OCE update pointed out that, “Based on ARMS data, 77.2 million acres of corn were planted in 2005, 81.9 million acres were planted in 2010, and 86.9 million acres were planted in 2016. The regions with the highest acreage were the Corn Belt, the Northern Plains, and the Lake States.”

More narrowly, the authors noted that, “On corn acres where nitrogen was applied, mean application rates increased between 2005, 2010 and 2016 in the three major production regions.”  (See graph below).

“For nitrogen per bushel, mean application rates decreased between 2005 and 2016 in the three major production regions.”  (See graph below).

Precision Agriculture

The OCE update noted that, “Precision agriculture includes the use of various technologies, such as tractor guidance systems using a global positioning system (GPS), GPS soil sampling, and GPS yield mapping. These technologies help farms gather information on field conditions and site-specific within-field limitations and allow for adjustments to production practices, such as variable-rate technology (VRT) for the application of inputs (fertilizer, seeds, irrigation water, pesticides). Potential benefits of precision agriculture include reduced inputs resulting in cost reductions, more efficient use of production inputs, and significant environmental benefits such as improved soil and water quality and reduced GHG emissions.”

The OCE fact sheet explained that, “The percentage of acres grown using variable rate technology (VRT) for nitrogen application increased for both corn and wheat production at the National level.” (See graph below).

Cover Crops

The authors pointed out that, “Cover crops are not harvested and are typically grown either during fallow periods (when harvested crops are not grown) or grown simultaneously with main crops (such as in an orchard or vineyard, called intercropping).”