Soil Layers and How They Relate to You

We all know there are different layers in the dirt outside. In simplest terms, there are five layers, each getting thicker and more condensed the deeper you go. But how is this relevant to you?

Top Layers

Humus

Soft, organic soil that is vital to plant growth. It varies by location how deep it can go. Typically about six inches but can be much more shallow in some places. When gardening or planting any tree or shrub, dig past this layer but be sure to return as much of it as you can to aid your plant's growth.

Topsoil

Nutrient and mineral rich layer that is much more dense than the layer above it. There may be rocks or a dense highway of roots (depending where you dig). When plowing a field or garden, it is important to turn this soil, it's about six inches to a foot deep.

Subsoil

Much denser, less life. There is much less organic matter in this layer than the topsoil. Here, clay, rocks, even a sandy-like silt makes up most of the composition.

JC Tree Service When some trees fall, it's because of a shallow or damaged root system. If the weight of the tree is anchored in this layer, it will fall when the weight is too much.

JC Grading This layer is typically removed during the rough grade process and returned with the final grade.

JC Construction These layers are too soft to give support to a beam that may have a lot of weight on it, so it's removed when necessary to dig for the harder layer below.

Bottom Layers

Weathered Rock Fragments

A couple of feet or deeper, this layer is made of mostly rock and hardened clay. It can be very sturdy if not disturbed. Digging to this layer will require a strong back or machinery.

JC Tree Service The deepest roots will penetrate this layer. If the tree is removed and the roots remain, the roots will shrink, decay, die, and leave a void. This is rarely becomes a problem but interesting to know.

JC Grading Removing all soil and grading to digging to this layer means either the soil layer was shallow or the project area needed to be significantly lowered to begin a build on a hard layer. Topsoil and Subsoil is added or backfilled during the final grade process.

JC Construction Basements, footers, support posts/beams, are all in this layer. To access this, machinery is almost always required.

Bedrock

The deepest and by far hardest and most dense layer. It is often continuous rock that can only be excavated by machine. Rarely will work need to be done this deep other than extreme situations or specific drilling situations, like for a well.