Michael Teague

The best soils are used for growing crops Poorer soils are used for grazing

To be proficient plant or animal science, or even in agricultural mechanics, you must be knowledgeable of soil science.

Soils form when minerals “rocks” mix with  Organic Materials- decaying plants and animals  Water  Air  Sun

Factors Influencing the Formation of Soils 1. Rainfall Zoomable image under soil science folder

2. Temperature

3. Microbes, Worms- Decomposition of O.M. 4. Parent Material- minerals from which soil develops. May lead to a clay or sand soil. May lead to a light or dark soil. 5. Topography- steep slopes equal thin soil, level lands have little erosion and may receive soil from slopes. 6. Time Classes of Parent Material Residual- came from underlying rock. Examples: sedimentary, igneous, metamorphic Transported- wind, water, glaciers. Cumulose- organic in origin. Examples: peat and muck.

Soil Composition  25% Water  25% Air  5% Organic Matter  45% Mineral Matter Tell ofcompaction

Soil Terms  Infiltration=water moving into the soil.  Percolation= water moving through the soil.  Fallow= allowing the soil to rest, by not planting or grazing. Field Capacity= the point where the soil can not hold anymore water. In between gravitational and available Wilting= occurs when the plant cannot obtain water. In between available and unavailable. Permanent Wilt= occurs, if the plant cannot recover over night. This results in a dead plant.

Soil Water Losses

Organic Matter 1.Provides nitrogen and othe nutrients 2.Hold water in the soil Three Soil Particle Sizes 1.Sand- *largest in size *high permeability *low water holding capacity 2. Silt- *medium in size 3. Clay- *smallest in size *high water holding capacity *low permeability *expands and contracts It is good to have a mixture of all three particles.

Soil Color- surface soils are darker in color, than subsoils. This darkness indicates organic matter. Soil Texture- *Sandy soils will feel gritty, and do not form into shapes. *Clay soils are sticky and smooth, they form shapes easily. Soil Structure- is how the soil particles arrange themselves with other soil particles. *None- like sand in a hourglass *cloddy- dirt clod Good Soil Structure  Allows Percolation  Allows Root Growth  Slows Run Off  Holds H2O

Soil Horizons 1. O= organic layer 2. A= topsoil 3. E= eluvial 4. B= subsoil 5. C= parent material 6. R= bedrock

Natural Resources Conservation Service, NRCSNatural Resources Conservation Service, NRCS= is a government agency that concerns itself with soil and water. Pull out SCS books Soil Sampling= will determine the soil’s input needs of fertilizer and lime. Soil Sampling Notes  Sample uniform areas. A hillside would be a different sampling area, than bottomland.  Take 15 random samples from each area.  Sample should be 6 inches deep  Mix the samples from one area together, do not mix areas together.  Do not sample unusual areas. Like under a tree where cows may stand and defecate. Soil Sampling Tube

Erosion= is the removal of soil by water and wind. Erosion takes place when the vegetative ground covering is removed. Sheet Erosion Gully Erosion Steepness of Slope and Length of Slope both factor into the potential of erosion.

Methods To Reduce Water Erosion  Terraces- “speed bumps” for water  Strip Crops- alternating strips of sod and rowcrop crops.  Crop Rotation- switching from row crop to sod crop, from year to year.  Contour Farming- plowing and planting at the same elevation. Bench Terraces Strip Cropping and Crop Rotation Strip Cropping

Soil particles can hold water, the smaller the particle the greater the water holding capacity. “clay can hold more than sand” Soil Water 1. Gravitational= water that the soil particles can not hold and will drain by gravity. 2. Available= water that is held by the soil particles, but not so tight that the plant roots can’t get it. 3. Unavailable= water held by the soil particles so tightly that the plant can not obtain it.

Bottom Lands are 1)Wet soils 2)Fertile soils 3)High water table limits root growth. In periods of drought, when the water 4)Wet soils, warm slowly in the spring. Water Drainage 1) Ditch= above ground 2) Tile= subsurface method 3) Mole= subsurface channel, unsuitable in sandy soils. Tile Mole