Zachary M.

This week’s Blog Post was written by Zachary M., a Gobblers Alumni! He describes the different types of soils, and how tilling methods can help preserve top-soil.

Soils are an important part of the environment we live in. All of the food we eat has a connection back to the soil. One might be thinking, dirt is dirt, right? Well…there is actually three basic different types of soils. Those three include Sand, Silt, and Clay. Almost all soils are a mixture of the three, at least to some degree. That combination is called the soil’s loam. Ideal loam conditions are about 40% sand, 40% silt, and 20% clay. The reason being is because each part has different properties to them.

A soil sample I dug that shows the O, A, and B horizons.

The biggest difference between them is the particle size. Sand has the largest particle size, allowing good infiltration and minimal compaction. Silt is the median particle size. Clay has the smallest particles, which compacts easier and has a low infiltration rate. When compiled in a 40-40-20 ratio, each of their properties are well distributed and it creates the opportunity for healthy soil to form.

Healthy soil is characterized by a few things. Sufficient nutrient supply, a diverse range of microorganisms/other organisms, a good infiltration rate, and pore space are all important components to having healthy soil. Human activity has a high impact on soil health. We can affect it positively, by adding fertilizer to replenish missing nutrients and elements. Unfortunately we often negatively affect it by compacting it with heavy equipment or using pesticides that kill off microorganisms.

Nature can also degrade soils through things like erosion, but oftentimes erosion takes place because of human activity. Tillage is a very good example of this. Farmers rip up the soil with their equipment, and in the process destroy the roots and compact the soil. When it rains heavily, it washes away valuable topsoil. This is why no-till planting methods are on the rise because it is more beneficial to leave old root systems intact or utilize cover crops.

Two small samples that I set side by side to contrast the difference between the A and B horizon.

Soil is formed in some of the same ways it is destroyed. It is created from the parent material over time. The main five soil forming factors are biological components, topography, time, climate, and parent material. Once soil is formed is can be categorized at different levels called horizons. Soil horizons, in order from top to bottom, include: O (organic), A (topsoil), B (subsoil), C (parent material), and R (bedrock). The thickness and consistency of each layer varies between different soils.

All photos in this blog belong to the author.