Soil Science

What is the vertical cross section of the soil from the ground surface downwards to where the soil meets the underlying rock?

• Soil texture

• Soil profile

• Soil drainage

• Soil erosion

Which term refers to the proportion of sand, silt and clay sized particles that make up the mineral fraction of the soil? ( fineness or courseness)

• Soil Texture

• Soil Profile

• Soil Drainage

• Soil Erosion

Match the following: Soil Profile

• plow layer, surface layer, topsoil, most fertile layer, thickness indicates degree of erosion

• C-R horizon

• subsoil, color indicates internal drainage, zone of accumulation

• B horizon

• organic layer, darkest layer

• E horizon

• substratum, parent material: lowermost layer, bedrock

• O horizon

• subsurface layer, zone of maximum leaching, leached grey color

• A horizon

Match the following: Types of Particles

• smallest mineral particle

• Clay

• the largest mineral particle

• Sand

• medium sized mineral particle

• Silt

The FOUR things found in soil are mineral matter​ (a)   %, air​ (b)   % water,​ (c)   %, and organic matter​ (d)   %.

• 45
• 25
• 5

Match the following: Using the Ribbon Test to determine soil texture.

• No ribbon forms; the sample breaks into pieces less then 3/4 long. Soil feels smooth/talc like.

• Moderately Coarse textured

• No ribbon forms; the sample feels gritty and lacks smoothness.

• Coarse textured

• A ribbon forms easily and remains long and flexible.

• Medium textured

• A ribbon forms but breaks into pieces 3/4 to 1 inch long.

• Fine textured

• No ribbon forms; the sample is composed almost entirely of gritty material & leaves no stain.

• Moderately Fine textured

​ (a)   is the process of the water soaking into the soil.

• Infiltration
• Percoliation
• Percolation
• Permeable
• Moisture-holding Capacity

​ ​ (a)   is the downward movement of water through the soil.

• Percolation
• Moisture-holding Capacity
• Gravitational moisture
• Leaching

​ (a)   is a soil that allows water movement by infiltration and percolation.

• Permeable
• Leaching
• Infiltration
• Capillary moisture

​ (a)   is the ability of soil to retain water.

• Moisture-holding capacity
• Gravitational moisture
• Percolation
• Capillary moisture