Increasing the quality of a soil—enhancing it as a habitat for plant roots and beneficial organisms—takes a lot of thought and action over many years. Of course, there are things that can be done right off—plant a cover crop this fall or just make a New Year’s resolution not to work soils that really aren’t ready in the spring (and then stick with it). Other changes take more time. You need to study carefully before drastically changing crop rotations, for example. How will the new crops be marketed, and are the necessary labor and machinery available?
All actions taken to improve soil health should contribute to one or more of the following: (a) growing healthy plants, (b) stressing pests, and (c) increasing beneficial organisms. First, various practices to build up and maintain high levels of soil organic matter are key. Second, developing and maintaining the best possible soil physical condition often require other types of practices, in addition to those that directly impact soil organic matter. Paying better attention to soil tilth and compaction is more important than ever, because of the use of very heavy field machinery. Last, although good organic matter management goes a long way toward providing good plant nutrition in an environmentally sound way, good nutrient management involves additional practices. In this chapter we’ll focus on issues of organic matter management.
Because organic matter is lost from the soil through decay, washing, and leaching,and because large amounts are required every year for crop production, the necessity of maintaining the active organic-matter content of the soil, to say nothing of the desirability of increasing it on many depleted soils, is a difficult problem.
—A.F. Gustafson, 1941