University:
Sam Houston State University
Course:
GEOL 1405 | Geologic & Environmental Hazards
Academic year:

2022
Views:

468

Pages:

10
Author:

Clint W.

Soil Texture Sand it is the larges soil separate and is composed mainly of weathered grains of quartz. Sand is also gritty to the touch. Sand grains will not stick to each other. Soil Texture Sand What will sand do to the soil? It will improve the soil by improving the water infiltration and aeration Soil Texture Silt is the medium sized soil separated. Silt particles are silky or powdery to the touch Silt grains will not stick to one another just like sand grains. Silt is the best soil as it has the ability to hold large amounts of water in a form plants can use. Soil Texture • Clay – is the smallest size soil separate. – It is composed of tiny crystals – Clay is formed by chemical reactions between weathered minerals to form tiny particle of new minerals. – Clay will hold more plant nutrients than any other separate. – Clay grains will stick to one another. Soil Texture Pass out picture of triangle and lets see if we can classify some soils. Soil Texture Triangle Soil Texture 1. 40% sand 22% clay and 38% silt What is the soil classified as? Soil Texture 2. 90% sand 10 % clay and 25 % silt What is it? Soil Texture Lets go and texture some of the samples that we have. See if you can make a ribbon and with which one? Which one feels grittiest? Which one feel powdery? Soil Structure What are the three grades of structured soils? A. Weak structure: peds are hard to distinguish. Only a few can be separated from the soil. B. Moderate structure: peds are visible and can be handled without breaking up. C. Strong structure: most of the soil is formed into peds.