Unit 3 Flashcards
Compaction increases ……
Increases soil strength but inhibits root growth
Density =
Weight / Volume
Bulk Density is measured using what condition of soil?
Undisturbed, Dry Soil
What is the Bulk Density rating of soil that has restricted root growth?
1.6 g/m3
What is the bulk density rating of compacted soil?
2.0 g/m3
What texture is a soil that compacts easily?
Fine textured soils
What texture is a soil that doesn’t compact easily?
Coarse Textured soils
What influences the bulk density of soil?
- ability of the soil to function as structural support
- ability for water and solute movement
- soil aeration
What does High Bulk Density indicate?
- low soil porosity
- soil compaction
What is Soil Tilth?
The physical condition of the soil as related to its ease of tillage or cultivation
What is Soil Tilth often referred to as?
Soil Condition
What is Tilth dependent on?
It’s dependent on the stability of aggregates.
Define: Aggregate Stability
Ability of soil particles to continue to be held in a single mass or cluster
What are the factors that increase aggregation of particles?
Organic Matter
Limestone
Biological Activity
What are the factors that decrease aggregation of particles?
Sodium (Na) - it makes them fall apart
Yellow Soil =
Drainage Problem (usually a season problem)
Blue/Gray soil =
Serious drainage problem that needs to be addressed!
Red Clay =
Good aeration
Green Soil =
High levels of copper…which means low pH…
Black/Brown soil =
High in OM
White Soil =
No OM …. Sandy
What are some soil colors that are encouraged by well aerated conditions?
Red
Brown
Yellow
What are some colors encouraged by poorly aerated conditions?
Gray
Blue
What system is used to determine your soil color?
Munsell Color System
Where is the Munsell Color System used?
Anywhere in the world
Why did they change the name to Rutgers College?
Colonel Henry Rutgers donated $5000 to the school.
What did George H. Cook do that was so important? What year did he do it?
1840….He revised the New Jersey Geological Survey….which became the model for the U.S. Geological Survey
Average Bulk density of soil is ?
1.33 g/m3
