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Soil. Objective: I will be able to explain what soil is and why it is important by creating an illustration. What is soil?. Material which nourishes and supports growing plants includes rocks, water, organic material and air. How is soil formed?. Rocks rubbing together for many, many years
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Soil Objective: I will be able to explain what soil is and why it is important by creating an illustration
What is soil? Material which nourishes and supports growing plants includes rocks, water, organic material and air.
How is soil formed? Rocks rubbing together for many, many years Organic matter
What is our State…… • Soil….. • Jory • Rock….. • Thunder Egg
What is a Thunder Egg According to ancient Native American legend, when the Thunder Spirits living in the highest recesses of snowcapped Mount Hood and Mount Jefferson became angry with one another, amid violent thunder and lightning storms they would hurl masses of these spherical rocks at each other. The hostile gods obtained these weapons by stealing eggs from the Thunderbirds' nests, thus the source of the name "Thundereggs." A Thunder egg is not actually a rock. It is a structure, sometimes a nodule, sometimes a geode,
Why is soil important? It supplies water, nutrients, and a medium for plants Acts as a filter https://login.icevonline.com/mycourses/DUNDA002/lesson/143
What are the functions of soil? • Plant medium • Recycling system for nutrients • Habitat for organisms • System for water supply • Water purification • Support foundation • Heat storage • Decomposes organic material • Buffer of toxic compounds to the environment • Source of raw materials • Gene pool • Source of history
Video • iCEV Video soil formation and evaluation- important. • https://login.icevonline.com/mycourses/DUNDA002/lesson/143
What are Soil Horizons? • As soils develop they form layers called Horizons.
O O Horizon A • Layer of accumulated organic matter such as leaves, grass, twigs • Material can be in various states of decomposition • Generally dark in color E B C R
O A Horizon A • Topsoil • Generally it is the most productive horizon • High biological activity • Generally dark in color E B C R
O E Horizon A • Leached soils • Soluble minerals and organic material move out of this horizon • Generally a lighter “washed” appearance in color E B C R
O B Horizon A • Less amount of parent material break down and organic matter. • Often more course fragments (rock visible) • Varies in color from reds and yellows to browns and grays E B C R
O C Horizon A • The unconsolidated material that has been affected little by the soil forming processes • Course fragments present E B C R
O R Horizon A • Hard bedrock • 100% course fragments, also known as rock E B C R
Video • iCEV video Soil Fertility and Productivity
Assignment You will complete a soil profile on the left side of your notebook You must have each horizon in your profile Each horizon must be colored accordingly Include characteristics of each horizon
Soil Differs in: • Texture • Color • Structure • Consistence • Fertility and Productivity
Soil Texture • The way soil feels • Based on the relative proportions of each size of soil particle • Sandy loam, Silty loam, Sandy Clay loam
Why is soil texture important? • Influences many soil properties • drainage, water holding capacity, aeration, susceptibility to erosion, organic matter content, cation exchange capacity, pH buffering capacity, and soil tilth
Sand (0.05-2.00 mm) Silt (0.002-0.05 mm) Clay (<0.002 mm) Soil Texture - Relative Sizes of Soil Particles
Sand • Larger particles in the soil • Can be seen with the naked eye • Not fertile • Quick to dry out and are doughy • Drain quickly
Silt • Between sand and clay particles in size, medium size • Provide few nutrients to plants • Erode every easily • Moderate drainage
Clay • Smallest of the soil particles • Hold soil nutrients • Hold more moisture than either sand or silt • Dry out slowly • Become cloddy unless properly managed
What is loam? The Best of All Worlds • A soil type that contains all three particle sizes. • The most productive soil for farming crops • Has good water holding capacity (from clay) • Has good drainage (from sand) • Can be nutritious (from silt)
Soil Texture Lab That person go get 1 of each of the bowls from up from (sand, Silt, and Clay) Put the bowls in the center of the table NO ONE TOUCH THEM OR THE LAB IS OVER!!!! Once everyone is done another person bring the bowls back up from. Wait until everyone is done
Copy down the following Define the following words: Clay Sand Silt Using the cups filled with Sand, Slit, and Clay, describe what you see, feel, hear, ect.
12 Soil Texture Classes • Sand (S) • Loamy Sand (LS) • Sandy Loam (SL) • Loam (L) • Silt Loam (SIL) • Silt (SI) • Sandy Clay Loam (SCL) • Silty Clay Loam (SICL) • Clay Loam (CL) • Sandy Clay (SC) • Silty Clay (SIC) • Clay (C) Compositions of each of the 12 texture classes is defined by the USDA Soil Triangle
Using the Soil Triangle find the following soils: Has to equal 100% at the end!! Silty Loam Sandy Loam Clay Loam
Assignment Soil Triangle problems