The physical structure is the “house” for the microbes and other living organisms that make up the weight of that “average sized cow” that must be fed on each acre before the plants growing there can receive the nutrients they need to do their best. But if the soil does not already have this proper physical structure, then how can it be attained?
Once the characteristics from the amount of sand, silt and clay in a soil have been taken into account, the nutrient makeup of each soil then determines how much pore space that soil contains. In general, any soil with an overabundance of calcium will have too much air space and lose moisture more quickly. Soils with excessive potassium – most likely where a large amount of compost has been continuously applied -- tend to run together and keep water on top of the soil making it more prone to water runoff. Excessive sodium can cause similar problems.
Soils with excessive magnesium tend to exhibit extreme hardening when dry, and in clay soils it makes them extremely sticky when wet and more prone to deep wide cracking when dry. How does one deal with such variations that already exist, whether from natural or man made circumstances? The answer is not as hard as some would tend to make it sound. The key is in using the simple basic science of soil chemistry that determines proper soil structure.
Another excellent measure of proper physical structure of a soil is the biological aspects of that soil. The soil is alive but may not always contain enough of the living organism needed to maximize plant growth. When soils have less than 2.5% organic matter, the microbes trying to survive there are said to be on a starvation diet. Some consultants advocate adding various microbes to the soil to increase soil life. But it should be pointed out that when living conditions are right for soil microbes, they will be able to propagate properly and provide the desired beneficial results. And so how does a producer manage that on their own property if they do not have access to a soil microbiologist? Is such a thing even possible?
Here is another key to the questions asked at the end of the above paragraphs. It is the key to healthy, biologically active, productive soils and
vibrant healthy productive plants. The laws of chemistry can be used to correctly manage each soil and its nutrients, which in turn will create the proper physical structure for every soil, which then determines the quality of the environment for the living organisms in the soil. The effect of proper soil chemistry on the ideal physical structure of the soil builds “the house” required for the biology. Using good sound soil chemistry to balance the nutrients needed for proper growth will actually change the porosity of each different type of soil to provide the ideal physical structure (allowing the correct amount of air and water and nutrients to be present), which then provides the correct environment to best benefit the biological life in the soil, including plant roots. The plants growing there are then fed and grown properly, producing more optimum growth and healthy plants.
This can be accomplished by taking soil samples properly for analysis and recommendations. However, these determinations are not made based on the number of pounds of each nutrient a soil may contain. It is determined by measuring the percent makeup of each element in terms of the soils total nutrient-holding capacity. If there is an excess of one or more of the elements mentioned above, there will be a deficiency of one or more of the others. This is the true meaning of balanced productive soil.
The first step to consider is to supply what is deficient to most efficiently begin to control what is excessive. The correct interpretation and use of such information is a key to healthy soil and productive healthy land.
<<To be continued in October issue>>