Soils and Hydroponics Management Unit 9 AgriScience 1

Media definition: material that provides nutrients and support through plant root systems. Plant Growing Media

Soil Defined: Soil is the mineral and organic matter that supports plant growth and is a mixture of rock particles, organic matter, living forms, air and water. Air Mineral matter- 45% Water OM5%

Soil- Planet Earth Land- 33.3% Water- 66.7%

Soil- Agricultural land Water- 66.7% Non Ag 24.4% Grazing-5.7% Water- 66.7% Non Ag 24.4% Ag – 8.6% Crops- 2.9%

Soil- Land Use in IOWA Crop- 74.3% Pasture- 12.7% Grazing-5.7% All Land- 93.7% Land in US- 6.2% Forest 4.9% Minor 2.7% Transportation 3% Iowa- .1%

Soil-less Media Media Mixes Perlite Vermiculite Peat moss Sphaghnum moss Sand Compost Wood chips, barks Water- Hydroponics

Soil Formation Climate Living Organisms Parent Material Topography Time Weathering

Climate Temperature Chemical reaction rates Growth of fungi, bacteria, plants Rainfall Increases erosion rate Increases leaching

Living Organisms Decomposers- fungi and bacteria- aid in organic matter breakdown. Plants- add organic material to soil Earth worms- help create soil structure and breakdown plant residue.

Parent Material Residual Transported Mineral Organic Glacial till-ice Igneous Sedimentary Metamorphic Organic Peat Transported Glacial till-ice Alluvial- water Loess- wind blown Colluvium- gravity added by water Lacustrine- lake deposits

Topography

Time Organic matters decreases and more leaching occurs Organic matter builds up soil becomes more productive Young to old soils

Weathering

Identifying Land Areas and Capability Legal description-location Old-Use a Soil Survey NEW-Digital Map resources

Legal Description A legal method of describing property for recording on deeds. 2 major systems used Metes and Bounds Rectangular survey

Metes and Bounds Used in the East and Southwest in early settlement. Uses major landmarks as a marking system. Many disputes when landmarks changed.

Rectangular Survey Adopted in 1875 Latitude and longitude based. Baselines and principal meridians 5th meridian is our principle meridian.

Townships Laid out starting at the intersection of principle meridian and baseline. 6 miles square 50 feet shorter on the north boundary. Correction lines every 24 miles

Townships 36 square miles 1 mile square each numbered

Sections 1 square mile 640 Acres further subdivided and described by halves and quarters

Build a Legal Description Start with smallest fraction section township county State

Land Capability

Land is more than soil Natural and artificial characteristics of an area to be used for agricultural or other purposes Includes renewable and nonrenewable resources plus improvements

Land The surface of the earth not covered with water Maybe temporarily or permenently covered with water A pond for aquaculture is considered land

Cropland Used for growing crops Crops grown typically improve the tilth of the land

Arable land Land that can be used for row crops Can be tilled Alternatives include pasture and forest crops

Major Characteristics of Cropland Soil - Large impact on productivity. Soil texture, nutrients and internal structure Climate - average of water conditions over a long time Topography - form or outline of the surface of the earth Water supply - amount of water available for crops

Subsurface conditions - Soil textures, hardpans Pollution - can prevent plant growth

Alternative Uses Best land use is determined by how the land will give the most benefits to people. Which use will give the highest returns What will happen if productive cropland is used for other purposes?

Land Improvement Four common practices to improve arable land Irrigation Erosion Control Drainage Forming (land forming)- surface is smoothed or reshaped.

Capability Factors Characteristics of land that determine its best use Surface texture proportion of sand, silt, clay down to about 7 inches three major classifications sandy loamy clayey

Soil Tilth Physical condition of the soil that makes it easy or difficult to work Poor tilth has hard clod Maybe very wet or very dry

Internal drainage Permeability- movement of water and air through soil Directly related to nutrient content Classified as very slow, slow, moderate and rapid water quickly soaks into sandy soil with high permeability soils with clay have slow permeability

Soil Depth Thickness of the soil layers Requirement depends upon type of crop to be produced Four soil depths are used very shallow - less than 10 inches shallow - 10 to 20 inches moderately deep - 20 to 36 inches deep - over 36 inches Shallow soils are often the result of erosion

Erosion Loss of topsoil by wind or other forces Four categories very severe erosion- 75% or more and large gullies are present severe erosion - 75% of soil has eroded but no large gullies present moderate erosion- 25 to 75% of soil has eroded with small gullies present none to slight erosion - less than 25% of soil has eroded and no gullies are present

Slope The rise and fall of the elevation of the land Measured in percents Important in determining the best use of the land

Surface Runoff Water from rain, snow, or other precipitation that does not soak into the ground Can be reduced by conservation practices chopping stalks terraces ground cover

Land Capability Suitability of land for agricultural uses. Usage should not cause damage to the land although nutients maybe removed

Land Capability Classes Assigning a number to land Eight classes used I to VIII with I being the best arability Class I to IV can be cultivated V to VIII tend to have high slope or low and wet

Classes Class I - Very good land Class II - Good land Very few limitations deep soil and nearly level can be cropped every year as long as land is taken care of Class II - Good land has deep soil may require moderate attention to conservation practices

Class III - moderately good land crops must be more carefully selected often gently sloping hills terraces and stripcropping are more often used Class IV - fairly good land lowest class cultivated on hills with more slope than class III Class V - Unsuited for cultivation can be used for pasture crops and cattle grazing, hay crops or tree farming often used for wildlife or recreation areas

Class VI - Not suited for row crops too much slope usually damaged by erosion with gullies can be used for trees, wildlife habitat, and recreation Class VII - Highly unsuited for cultivation has severe limitations permanent pastures, forestry, wildlife slope is usually over 12 percent large rock surfaces and boulders may be found very little soil present

Class VIII Cannot be used for row crops or other crops often lowland covered with water soil maybe wet or high in clay aquatic crops maybe grown there used for waterfowl habitat

Physical, Biological, and Chemical characterisitics Unit 9

What is a Soil Profile?- a view of a cross section of soil 0 Horizon-located on surface, mostly O.M. A Horizon-Called Topsoil, good amounts of O.M. and minerals. B Horizon- Known as Subsoil, Less O.M. C Horizon- Mostly parent material, does little for plant growth. R- bedtrock

Soil Profile- Differences in layers based on: Organic matter Texture Color Structure

Soil Color Determined by 2 main things Organic matter Mineral content

It is the relative sizes of the different soil What is soil texture It is the relative sizes of the different soil particles.

The major Soil Texture Classes Sand-largest particle Silt-medium size particle Clay-smallest particle

Characteristics of aSandy Soil

Characteristics of a Silty Soil

Characteristics of a Clay Soil

Using the Soil Texture Triangle

What is Soil Structure? Sand, silt and clay particles combine with one anther to form cluster called aggregates. The way in which aggregates or clusters are arranged is referred to as soil structure.

Soil Structure Categories

Media Amendments

Terms and definitions Essential Nutrient- Element necessary for plant growth and reproduction, for example: nitrogen, phosphorus, and potassium. Deficiency- Plant condition where an essential nutrient is not sufficiently available. Symptom- A visual sign or condition that results from a deficiency: symptoms aids in diagnosing a deficiency.

Chemical Elements Essential To Plant Growth Non-mineral- air and water Carbon (C) Hydrogen (H) Oxygen (O) Nitrogen (N) Mineral- from the soil Primary Nitrogen (N) Phosphorus (P) Potassium (K) Secondary Calcium (Ca) Magnesium (Mg) Sulfur (S) Micronutrients Iron (Fe), Boron (B), Manganese (Mn), Copper (Cu), Zinc (Zn), Molybdenum (Mo), Clorine (Cl)

10 Essential Elements Essential Elements Carbon (C) Hydrogen (H) Oxygen (O) Phosphorus (P) Potash (K) Nitrogen (N) Sulfur (S) Calcium (Ca) Iron (Fe) Magnesium (Mg) C. HOPKINS CAFÉ Mighty Good

Functions of Nutrients for plant growth Carbon, Hydrogen, and oxygen are needed in the plant processes of photosynthesis of photosynthesis and respiration. Approximately 95% of weight of plants comes from products of photosynthesis

Primary Nutrient Functions Nitrogen (N) Gives green color to plant Induces vigorous , rapid growth in plants Increases protein and yield Aids and promotes seed and fruit development Nitrogen constitutes 80% of the atmosphere, yet it is one of the most critical elements for plant growth. Plants cannot utilize N as a gas, it must be combined with other elements.

Primary nutrient deficiency symptoms Nitrogen (N) Stunted and Spindly Yellow, yellowish green or light green in color in foliage (chlorosis) Older leaves affected first, starting at the tip and moves along the middle of the leaf.

More Primary Nutrient Functions Phosphorus (P) Important to germinating seedlings Contributes to early maturing crops Necessary for seed and fruit formation Stimulates root growth

Primary nutrient deficiency symptoms Phosphorus (P) Stunted Growth Very dark green color Purple leaves or portions of leaves in advanced stages Older leaves affected first

Primary Nutrient Functions Cont. Potassium (K) Necessary for production and translocation of carbohydrates Produces plumper seeds Controls Water intake and respiration Stiffens straw and stalks

Primary nutrient deficiency symptoms Potassium (K) Shorter plants Bronzing or browning of leaf color Lodging (bending of the stem) occurs Leaves show yellow to brown coloring along leaf margins followed by complete browning.

Deficiency Continued Other conditions besides deficiencies may cause abnormal plant growth. Cold, wet weather, lack of sunlight, disease, insect damage, and improperly applied chemicals are examples.

More Terms and Definitions Fertilizer- Natural, manufactured, or processed material or mixture of materials that contains one or more of the essential nutrients; availible in: dry form liquid form gaseous form

Fertilizer Terms Analysis- Percentage water soluble content of nitrogen (N), phosphorus (P) expressed as P2O5, and potassium (K) expressed as K2O in the fertilizer. Brand- Trademark of the company which produced the fertilizer. Complete Fertilizer- Fertilizer which supplies all three primary nutrients, (N,P,K)

Factors that Influence Fertilizer Use Chemical and physical condition of the soil Crop to be grown Climatic Conditions Time

Growing plants without a soil media. Hydroponics

Hydroponic methods Aggregate culture Nutriculture Aeroponics Continuous flow culture

Aggregate culture

Nutriculture

Aeroponics

Continuous flow culture