Soil

Soil Components

Solid support
Organic - chemicals with carbon
Inorganic - chemicals without carbon
Air including oxygen
Water
Organisms!! 1 acre-foot = 3 tons of organisms!

Inorganic particles

Rock
Gravel (ignore these for now but important in New England)
Soil Horizons:

black A leaching zone - organics here - most roots lost by erosion, esp. tropical soils
red B accumulation zone - nutrients collect here
rocky C weathered bedrock
solid D bedrock

Erosion Prevention: Proper Cultivation, Mulching, Perennial Planting!

Size Drainage Water Retention Air Nutrient Capacity
Sand 1-0.1 mm +++ 0 +++ 0
Silt 0.1-0.001 + ++ ++ ++
Clay < 0.001 0 +++ 0 +++

Need a mixture of these for optimum soil texture = LOAM

black	A	leaching zone - organics here - most roots	lost by erosion, esp. tropical soils
red	B	accumulation zone - nutrients collect here
rocky	C	weathered bedrock
solid	D	bedrock

	Size	Drainage	Water Retention	Air	Nutrient Capacity
Sand	1-0.1 mm	+++	0	+++	0
Silt	0.1-0.001	+	++	++	++
Clay	< 0.001	0	+++	0	+++

H₂O + Calgon	Surfactant = surface active agent sodium hexametaphosphate breaks up clumps separates particles

Clay 3.0 cm Total = 10 cm 30% Clay Sandy Clay Loam
(from triangle below) Sandy = drainage + air
Silt 2.0 cm 20% Silt Clay = nutrients
Sand 5.0 cm 50% Sand Loam = good for plants

Clay 3.0 cm	Total = 10 cm	30% Clay	Sandy Clay Loam (from triangle below)	Sandy = drainage + air
Silt 2.0 cm	20% Silt	Clay = nutrients
Sand 5.0 cm	50% Sand	Loam = good for plants

Organic Particles

rotting material = humus

^drainage
^nutrients
^water capacity
sources

leaves
grass clippings
compost
green manure
manure - esp. Horse

Go back to the Course Schedule.