To be a successful range manager, you need to know a great deal about the range. The things that make up the range are soils, water, and plants. A practical knowledge of each is essential for knowing your range.

The Soil

The material from which soil is formed is called the parent material. Soil is formed by the action of climate and living things, as conditioned by the slope of the land. There are many kinds of soil, differing in parent material, depth, color, texture and structure. These soil characteristics are called physical features.

For Information on Biological Soil Crusts: Soil Biological Communities ; Soil Biological Crusts

For Information on Rangeland Soils: Rangeland Soil Quality

Physical features
Soil depth. The amount of soil above the parent material determines the soil depth. It takes millions of years for bare rock to be turned into rich, fertile soil that will support plants and animals. Soil is made up of layers, with the dark topsoil the most important to the range manager. It takes about 500 years to build 1 inch of soil from bedrock. When the topsoil is bare of plants, it will be eroded by water and wind. Washing and blowing wastes the fertile topsoil. Soil depth is an important factor in determining what kind of plants will grow on the soil.

Texture. The size of the various soil particles within each soil layer indicates the texture. Bedrock first breaks down into large rocks, then into smaller rocks and pebbles. As weathering continues, the pebbles are broken down into small particles until we have a fine textured soil. The kind of parent material, as well as time, influences the texture of the soil. Soil particles have the following names, based upon their size: gravel, sand, silt and clay.
Our soils are a mixture of the different-sized soil particles. The name given the soil is based partly on the size of the particle that is most abundant in the soil. For example, very fine, sandy loam means that the soil is made up mostly of very fine sand particles, with some silt and clay particles. Approximate soil texture can be determined by ‘feeling’ the soil.

Structure. The soil particles are grouped together like ‘grains’ of a popcorn ball. The structure of soil is determined by how the particles are grouped. Soil with good structure readily takes in water and stores it for plant use. Good soil structure is associated with soil productivity.

Color. Color is also an important factor used in describing soils. Soil color is determined by the parent material from which the soil was formed, by climate and by the amount of organic matter in the soil. Color is sometimes considered to be a reflection of soil productivity. For example, a dark black color generally indicates a highly productive site.

Soil Slope. The slopes of land are extremely variable, from slightly rolling to steep hills and mountains. Steepness of slope is an important factor influencing soil depth. Other factors, such as position on slope and rate of soil formation, also influence soil depth. Generally, the steeper the slope, the more rapidly erosion may occur, thus reducing soil depth.

Organic Matter. Rangeland plants and animals become a part of the rangeland soils as they die and decompose. Leaves dry and drop to the soil, protecting the surface. Roots die and furnish food for millions of living plants and animals called soil organisms. These organisms are constantly working the soil materials into a form that plants can use. Usually, the more organisms there are in the topsoil, the better the vegetation.

To keep the soils productive for the future, it is necessary to return something to the soil. At the end of the growing season vegetation should be left in a healthy condition to help reduce erosion and increase water intake. When grazing animals remove too much vegetation, expensive soil conservation practices such as upland and riparian restoration and reseeding native grasses may be needed to hold the soils in place. It is better land management to graze properly than to rely on artificial practices to prevent soil erosion.