Soils Lecture 1 Flashcards
What are the properties of the “A” horizon?
- A is the TOPSOIL
- Dark do to to OM-
- Leaching of iron, Clay, and other minerals (eluviation)
- Primary ROOT ZONE
- High in micro organisms
- An AP horizon is one that has been plowed (often contains some of the B horizon)
What are the properties of the “E” horizon?
- E for ELUVIATION
- Lighter colored zone beneath the A horizon
- OM, clay, iron, etc. has leached out
- Zone of GREATEST ELUVATION
- Most often found in high sand soils
- Not found in all soils
What are the properties of the “O” horizon?
- O for Organic Material
- Some of the leaves and recognizable litter as well as the duff (the unrecognizable OM)
Solum
- A, E, & B horizons
- where most soil forming occurs
- also where nearly allroot growth occurs
What are the properties of the “B” Horizon?
- subsoil
- zone of illuviation (or accumulation)
- low OM
- higher clay and iron
- when clays have substantially illuviated here it is named Bt
- hardpans can form here
What are the properties of the “C” horizon?
C is for zone of parent material – usually with some fragments of partially weathered bedrock (or little changed glacial till) – taprooted plants and prairie species may root here
What are the properties of the “R” horizon?
R is for rock – bedrock or parent material unaffected by weathering and with very little
root affect
What are the properties of an “Ap” horizon?
Land that has been plowed
Capillary Action
-water will climb a very narrow tube on its own
because of the pull of water tension
-this allows trees to get water to great
heights and blood to flow through our smallest blood vessels
-water tension also helps to hold clay together so tightly
Loam
-a mix of nearly equal amounts of the three soil texture characteristics (sand, silt, clay)
Soil Tilth
Tilth is technically defined as the physical condition of soil as related to its ease of tillage, fitness of seedbed, and impedance to seedling emergence and root
penetration.
Friable
a description of how crumbly a soil is
Tilth
health of a soil based on its structure, looseness, and potential of root penetration
Loam
a suitable mix of sand, silt, and clay
Leaching
loss of minerals in a horizon by water action
Eluviation
particles or minerals EXITING a soil horizon
Illuviation
particles or minerals moving INTO a soil horizon
Humus
unrecognizable organic matter
Solum
the A and B Horizons
Porosity
open space in soils for water or air
Salinization
build up of salts in soil
Decomposition
break down of complex mater into simpler (usable compounds)
Mineralization
breaking Organic matter into usable mineral nutrients
Soil Tilth
Tilth is technically defined as the physical condition of soil as related to its
-ease of tillage
-fitness of seedbed
-impedance to seedling emergence and root
penetration.
The health of a soil based on its structure, looseness, and potential of root penetration is called ______.
Tilth
The process of breaking organic matter into usable mineral nutrients is called _______.
Mineralization
The process of breaking down complex mater into simpler (usable compounds) is know as _______.
Decomposition
Test Q: Roots require what one thing that most people don’t realize?
Oxygen
Test Q: Distinct layers in soil are known as?
Horizons
Test Q: What element is the principle component of organic matter and is the basis of all organic life?
Carbon
Test Q: Name two purposes or uses for soil besides growing crops.
Filtering water, Building on…
Test Q: Why does clay get so sticky and hold together so well?
- It’s made up of tiny flat particles that have a lot of surface area
- It has electrical charges that hold particles together
- It holds water better than silt or sand
Soil Mottling
Irregular marked spots in the soil profile that vary in color, size and number.
EX: Reddish iron spots
Test Q: Mottling in a soil is an indication of what?
The soil is not well drained
Test Q: Which of the following layers may not be in very many soils?
An E that is light colored
Test Q: When doing the ribbon test to soil, a ribbon consisting of 4 inches tells you the soil has a lot of?
Clay
Test Q: Which habitat should you find the deepest and richest A horizon in?
A Prairie
Test Q: Which of these will settle out of a soil and water solution first? • Silt •Clay •Organic Matter •Sand
Sand
Test Q: Mycorrizae are ….?
Fungi hairs that have a symbiotic relationship with plants
Test Q: The perfect combination of sand, silt, and clay in soil is known as …?
Loam
Test Q: In the day plants produce oxygen by photosynthesis, what do they do at night?
Respire, take in oxygen and and give out Carbon Dioxide
Test Q: On a fertilizer bag the N-P-K content tells you what?
It has Nitrogen, Phosphorus, and Potassium
