Therefore, a precise analysis of nitrogen is more difficult to obtain. Most university soil test labs do not routinely test for nitrogen. Home testing kits often contain a test for nitrogen which may give you a general idea of the presence of nitrogen, but again, due to the various transformations of nitrogen, the reading may not be reliable. Organic matter is often part of a soil test. Soil organic matter is highly desirable.
Organic matter has a large influence on soil structure.
Good soil structure improves aeration and water movement and retention. This encourages increased microbial activity and root growth, both of which influence the availability of nutrients for plant growth. Soil organic matter also affects the availability of plant nutrients and how pesticides react in the soil. Soils high in organic matter tend to have a greater supply of plant nutrients compared to many soils low in organic matter. Organic matter tends to bind up some soil pesticides, reducing their effectiveness.