Because of its weak structure, overly tilled soil will lose integrity, or fall apart quickly, and crust when exposed to rainfall. Soil with more organic matter and surface residue, however, will remain stable and will not crust. The key for improving soil structural stability is to produce plenty of roots and residue and leave it intact, Hubbs said. Mike Hubbs collects core sample for bulk density while waiting on respiration test. Infiltration Rate Infiltration rate, the rate at which water moves into the soil surface, correlates with organic matter levels, earthworm numbers and soil stability.
Good infiltration reduces erosion and helps keep vital topsoil and organic matter in place.
In addition, water that infiltrates into soil is less likely to run off fields and carry soil, nutrients and chemicals to nearby water sources. Excess salts, which may occur naturally or as a result of management, inhibit plant growth and disturb the soil-water balance. Any process that changes the soil-water balance may affect the movement and accumulation of salts in the soil, Hubbs said. And, when excess water on the soil surface evaporates, salts accumulate on the surface. Practices to reduce excess salts include irrigation management, crop rotations, manure application, and conservation tillage, all of which improve infiltration and permeability.