There are many things to be learned by regularly observing the soil and plants in your fields. These include being able to evaluate the severity of runoff, erosion, and compaction; root development; severe nutrient deficiencies; and the presence of earthworms, among other things. Laboratory evaluations of biological indicators, as well as more comprehensive evaluations of indicators of soil health, can also be employed. It is, of course, not enough to know whether a particular limitation exists. In the following (and last) chapter we will discuss both how to put together soil and crop management systems for building healthy soils and how to address particular issues that may arise from field observations or laboratory analyses.
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