1. Soils and Hydroponics Management
Ag. Chapter 9
Soils and Hydroponics Management

3. Mediums (media) – surrounding environment in which something functions and thrives Principal types of media: oceans rivers land man-made mixtures

4. Hydroponics: the process of growing plants without soil
Other types of media:
compost (dead & decomposed organic matter)
leaf mold
Sphagnum (types of moss)
Peat moss (partially decomposed moss)
Perlite (natural volcanic glass)
Vermiculite (mineral used for starting plant seeds and cuttings)

5. Soil
What is soil?

6. Soil is the top layer of the Earth’s surface, suitable for its growth.

7. What is the purpose of soil?

8. The purpose of soil is to hold seeds in place, and to hold water until the roots of plants/trees can extract the water from the soil.

9. How is soil formed?

10. 1. Climate and location – Temperature, rainfall, slope, and location of a field have a huge affect on the formation of soils.
As temperatures rise, the chemical reactions, growth of fungi, organisms, and plants increase.
Too much rainfall can remove nutrients from the soil and create an acidic soil.
The slope of the land determines how badly and how quickly the soil will erode.

11. Living organisms – such as microbes, plants, insects, animals and humans all cause soil formation by mixing various layers of the soil materials. Living organisms break down organic matter in materials that plants can use over time. Human activities can include cultivation, dozing, and construction. The tend to greatly disturb surface soil layers.

12. 3. Parent material – horizon of unconsolidated material from which a soil develops. Soils are broken down into horizons.
Soil Horizons:
O – Surface Organic Material
A-Horizon – Topsoil
E – Elluvial layer
B-Horizon – Subsoil
C-Horizon – Parent material
R-Horizon -- Bedrock

13. Soil horizons can be shifted and moved by various methods
Soil horizons can be shifted and moved by various methods. Alluvial Deposits – deposited by streams Lucastrine Deposits – left by lakes Loess Deposits – left by wind Colluvial Deposits – shifted by gravity Glacial Deposits – deposited by ice

14. Topography – has to do with slope and drainage
Topography – has to do with slope and drainage. Soil material is moved downward by runoff water, gravity, and the movement of humans and animals.
Slope also affects how much water soaks into the soil. The greater the slope of a given area, the less water will soak into the ground.
On level areas, the soil has a greater percolation rate (water soaks in and moves through the soil).

15. 5. Time – Soils are formed by all the previously mentioned factors over time.

16. 6. Weathering – the mechanical forces caused by temperature, cooling, freezing, and thawing. Rocks, minerals, organic matter, and other soil-forming materials are broken down into smaller and smaller particles until soil is formed.

17. Soil classification – soils are grouped according to their physical, chemical, and topographical aspects.

18. Land capability classes
Class 1 – soils have few limitations that restrict their use.
Class 2 – soils have moderate limitations that reduce the choice of plants or require moderate conservation practices
Class 3 – soils have severe limitations that reduce the choice of plants, require special conservation practices, or both.
Class 4 – soils have very severe limitations that reduce the choice of plants, require very careful management, or both.

19. Class 5 – soils are not likely to erode, but have their limitations, impractical to remove limitations, that limit their use. Class 6 – soils have severe limitations that make them generally unsuitable for cultivation. Class 7 – soils have severe limitations. Almost unsuitable for any type of plant production Class 8 – soils have such severe limitations that they cannot be used for anything except recreation and wasteland.

20. Factors limiting capability classes: Surface texture: sand, loam, or clay Organic matter: Thickness of rooting zone: Permeability: Rapid, Moderate, Slow Slope: Nearly level, Gently sloping, Moderately sloping, Strongly sloping, Steep, Very steep Erosion: None to slight, moderate, severe, very severe Runoff: Poor, somewhat poor, moderately well and well, excessive

21. Physical, chemical, and biological characteristics:

22. O A B C 1. Soil profile - Organic Topsoil Subsoil
Horizon
Name
Colors
Structure
Processes occurring O
Organic
Black, Dark brown
Loose, crumbly, well broken up
Decomp. A
Topsoil
Dark brown to yellow
Generally loose, crumbly, well broken up
Zone of Leaching B
Subsoil
Brown, red, yellow, or gray
Generally larger chunks, may be cement-like
Zone of accumulation C
Parent Material
Variable, depending on parent material
Loose to dense
Weathering, disintegra-
tion, of parent or rock

23. Particle size and texture
Sizes of Soil Particles
Name Size, Diameter
in Millimeters
Fine Gravel – 1
Coarse Sand – 0.50
Medium Sand – 0.25
Fine Sand – 0.10
Very Fine Sand – 0.05
Silt – 0.002
Clay less than 0.002
Clay
Silt
Sand

24. Structure Sand Loamy sand Sandy loam Loam Silt loam Clay loam
Silty clay loam
Sandy clay loam
Clay

25. Organic matter
Examples: roots, algae, fungi, actinomycetes

26. Living organisms Make the soil porous Supplies nutrients Holds water
Manages moisture content
Minimizes leaching
Stabilizes soil structure

27. Soil pH
Some plants grow better at different soil pH. pH is the measure of acidity in the soil. Anything below 7 is considered acidic. Anything above 7 is considered alkaline.

28. How do I determine soil pH?

29. Soil Samples
The process for taking a soil sample are on page 170 in your book. If you or your parents are interested in taking a sample from your property, let me know.

30. Soil tests
Petiole test – samples and tests the petiole (young stem and leaves) to determine which deficiencies might be present.

31. pH test – tests the acidity of the soil to determine what needs to be added and how much to raise or lower pH.
If your soil’s pH is too low, meaning the soil is too acidic, you will add lime.
If your soil’s pH is too high, meaning the soil has too much alkalinity, you will add gypsum.

32. Fertilizers

33. Organic – Manures, compost from plant/animal products
dried/pulverized manure, bone meal, tankage, blood meal, sludge, cottonseed and soybean meal.
High in nitrogen
Are only available as materials decay
Are NOT balanced sources of nutrients

34. Inorganic – Mineral salts
Minerals are in soluble form and quickly available to plants
Minerals can cause injury to plants if not used correctly
Should not come in contact with roots or stay on foliage
Concentrations are high in the nutrients they contain.

35. Fertilizer contents:
N – Nitrogen > promotes plant growth
P – P2O5 > Phosphorus (phosphate) >> promotes fruit, flower, and seed development
K – K2O > Potassium >> Root growth

36. How to put out fertilizer:
Broadcasting – spreading evenly over the entire surface
Band application – place fertilizer about 2 inches to one side and slightly below the seed. It is used for row crops in gardens and fields.
Side dressing – place fertilizer in bands about 8 inches from the row of the growing plants. Side dressing is used mainly for corn and soybeans.
Top dressing – broadcast fertilizer lightly over close-growing plants. Top dressing is used to add nitrogen to small grain, hay, and turf crops.

37. Using manure as fertilizer:
§ Use adequate bedding to absorb liquids
§ Balance phosphorous in cow manure by adding super-phosphate
§ Spread manure evenly over fields. 8 – 12 tons per acre
§ Incorporate manure into soil immediately after spreading
§ Do not spread on steep slopes when the ground is frozen
§ Keep manure compact and covered when in storage
§ Prevent liquid runoff when in storage

38. Amount of available nutrients per ton of manure:
Cattle Sheep Swine Poultry Horses
NITROGEN
PHOSPHOROUS
POTASSIUM

39. Nutrient deficiencies
Nitrogen deficiency
Potassium deficiency
Magnesium deficiency
Phosphorus deficiency

40. Hydroponics

41. Major Hydroponics Systems
Aggregate culture – sand, gravel, or marbles support the roots.
Water culture (solution culture, nutriculture) – plant roots are immersed in water containing dissolved nutrients
Aeroponics – plant roots hang in the air and are misted regularly with a nutrient solution
Continuous flow systems – nutrient solution flows constantly over plant roots (most commonly used)

42. Hydroponics offers an alternative solution in areas where soil is unsuitable for growth.

43. Water – Large plants may consume up to one gallon of water per day in a hydroponics system. Water needs to be clean and contain little salt. Too much salt will cause nutrient imbalances to occur in plants.
Oxygen – Plants need oxygen to carry out normal functions. In most hydroponics systems, oxygen is bubbled through the water.

44. Mineral Nutrients – Nutrients are supplied to roots through a diluted solution.
Necessary Macronutrients – nitrogen, phosphorus, potassium, calcium, and magnesium
Micronutrients – iron, manganese, boron, zinc, copper, molybdenum, and chlorine

45. Light – At least 8 to 10 hours of direct sunlight is needed per day
Spacing – Plants need space to grow and not reduce sunlight. Spacing varies depending on the plant.
Temperature –
Warm season: 60 to 80 degrees
Cool season: 50 to 70 degrees
Support – Plants must be anchored to prevent falling over.

46. Hydroponics is an increasingly important field of study
Hydroponics is an increasingly important field of study. As populations increase and fertile farmland decrease, hydroponics will be used more and more in the future.