What is the bottom line?
What is it worth to change to practices that enhance soil organic matter? Organic matter is one of the most important assets on a farm, yet it is difficult to attach a dollar value to it. Decreased fertilizer bills are measurable, but organic matter management touches on many aspects of the farm system that are not as easy to measure. Here is a checklist of costs and benefits to consider as you think about changing practices to improve soil organic matter.
- Time - How do the proposed changes affect your labor demands during each season?
- Yield - Yield changes are difficult to monitor because they vary with genetics and weather. As organic matter and biological activity increase, yield may increase as a result of decreased compaction, improved water availability and drainage, improved germination, improved root growth, improved availability of nutrients throughout the season, and reduced pests. Or yield may decrease, especially during the first few transition seasons, as a result of slower germination (due to increased residue delaying soil warming), or increased weed populations from decreased tillage.
- Crop quality - Feed or market quality may change as practices change.
- Skills and information required - Do you have the necessary knowledge or know where to find information about new practices?
- Soil loss - Practices that improve organic matter may also reduce erosion.
- Pollution - New practices will affect whether nutrients and pesticides leach through the soil or run off the surface.
- Inputs
- equipment: New purchases or rentals may increase equipment costs
- fertilizer: Organic matter additions may replace some fertilizer.
- pesticides: Decreased tillage may increase herbicide use. New rotations may eliminate the need for some insecticides or fungicides.
- seeds: A new cover crop may increase seed costs.
- Financial security - What is the reliability of the prices of new crops? How diverse is your income?
Set realistic goals
Have appropriate expectations as you consider changing organic matter management practices. Don’t expect rapid increases in total organic matter. Although an increase from two to three percent sounds small, it is a hefty fifty percent increase in organic matter, and will not happen quickly. But measurable increases in total organic matter can happen in the long term. Accept the upper limits of your soil and climate. For example, most sandy soils cannot hold more than two percent organic matter, but that two percent is valuable and important to protect.
As you monitor changes in organic matter, it may be less important to track total organic matter and more important to track evidence of improved active organic matter. Look for better soil structure, less crusting, or less susceptibility to drought. You may also see measurable improvements in pest problems or crop nutrient status. These changes may appear within two to three years of switching to new practices.
Soil Management Sections:
Introduction |
Soil Manager |
Soil Scientist |
What's Next |
Acknowledgments
