Agronomy and Horticulture Department



Soils - Part 3: Soil Organic Matter

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Plant and Soil Sciences eLibrary (PASSeL) Lesson


Copyright © 1999 Plant and Soil Sciences eLibrary. Used by permission.


In this lesson, you will learn such terms as organic, soil organic matter, nutrient, decomposition, humus, compost, and soil structure. In addition, you will be able to predict the effect of land uses on soil organic matter including the effects of different types of vegetation.

[This lesson, as well as the other nine lessons in the Soils series, is taken from the “Soils Home Study Course,” published in 1999 by the University of Nebraska Cooperative Extension.]


Why do we care so much about soil organic matter? Is it some vague favorable connection with organic farming? What does the term “organic” mean in a scientific sense? Fortunately, our instinct that soil organic matter is a good thing is well-founded. Under most circumstances, soils with more organic matter are superior to those with less. The reasons for this may not always be the same, but that only makes it all the more important to understand as many of the implications of soil organic matter content as possible.