Tool Calculates Organic Matter

Spreadsheet based calculator can help farmers improve production and save money while improving soil quality.

Published on: Mar 5, 2014

A new tool that allows farmers to easily predict soil organic matter content and can help them make decisions about whether or not to sell crop residue.

The tool, developed by researchers with Ohio State University's College of Food, Agricultural, and Environmental Sciences, enables farmers to plant and harvest in a more timely manner. That will help them reduce operating costs, increase farm income, and building healthier soils, says Rafiq Islam, the soil, water and bioenergy resources program leader at Ohio State University's South Centers in Piketon.

Tool Calculates Organic Matter
Tool Calculates Organic Matter

Called a soil organic matter calculator, the tool is designed to allow farmers to easily evaluate the impact of selective crop residue removal on the long-term agronomic and environmental integrity of their farm's soils, he says.

The calculator is also designed to help growers select management practices that conserve or build soil organic matter, says Islam.

"Farmers are aware that soil organic matter is the foundation of sustainable agriculture for enhanced ecosystem services," Islam says. "How you farm today will affect the amount of soil organic matter content your fields will have in years to come, so it's important to choose sustainable production practices that sustain soil health and protect long-term productivity." 

The soil organic matter calculator is a spreadsheet-based tool that consists of three primary worksheets that offer multiple options, including a user guide, data manager, a calculator for prediction of soil organic matter, a test scenario module and printed results, he says.

"The calculations are based on several factors including crop rotation, yields, tillage type, tillage depth, erosion rate, manure applications and cover crops," Islam says. "The calculator, which uses soil organic matter level at the beginning of the simulation period as the baseline parameter, can predict annual soil organic matter dynamics and parameters for up to 50 years.

"The outputs of the calculator consist of total, active and passive soil organic matter, total nitrogen and change in organic matter over the simulation period. The tool can also help calculate the revenue from residue sales and the amount of carbon emitted as carbon dioxide to the atmosphere or sequestered yearly or over the evaluation period."

More information is available online. Select "SOM Soil Organic Matter Calculator" under the Extension menu.