1. Soil Review Taking Soil Samples
Soils and You
Soil Review
Taking Soil Samples

2. Soils Define Soil Soil profile Soil structure Soil texture pH
Properties
Soil sample purpose
Where do they go?
When?
Procedures
Interpretation

3. What is soil? Top layer of the earth’s crust
Renewable natural resource that supports life
It takes thousands of years to make one inch of soil, naturally.

4. Soil Profile Layers are horizons Typical profile- O: organic, humus
A:topsoil, fertile, organic
B:subsoil
C: parent material
R: bed rock

5. Soil Structure How particles cluster together
Granular is best for most plants
Particle-Ped-Structure

6. What are the principle forms of soil structure?
Platy
Columnar
Granular
Prismatic
Blocky
Single Grained

7. What are the three grades of structured soils?
Weak- peds are hard to distinguish
Moderate- peds are visible and can be handled without breaking
Strong- most of soil is formed into peds

13. Discuss the effects of soil structure on crop production?
With good structure, roots can grow more easily.
Water can drain and be stored.
Nutrients can be harvested by plants- accessible.

14. What are the advantages of good soil structure?
Good drainage
Good air movement
Less erosion

15. What are the results of poor structure?
Poor drainage
Less air movement
Erosion
Decreased plant growth

16. What are some causes of poor soil structure?
Compaction- tractors, livestock, people
Tilling wet or muddy fields

17. What can we do to create and maintain good structure?
Use no-till more often
Make fewer trips in the fields
Do not till wet soil
Rotate with fibrous rooted crops
Cover crops

18. What is soil aeration?
Soil aeration relates to the exchange of air in the soil with air from the atmosphere.

19. Define soil tilth.
It is the physical condition of the soil as related to tillage, seedbed preparation, seedling emergence, and root penetration.

20. Soil Texture Size of particles Clayey-small, high WHC
Loamy-about equal parts of sand, clay and silt (ideal)
Sandy-large particles, low WHC

21. WHC This is known as water holding capacity
The larger the particle the lower the WHC
Sand doesn’t hold water, right!

22. What are the physical characters of the soil that determine its suitability for plant growth?
Texture
Consistence
Structure
Aeration
Tilth
Moisture

23. What does soil texture affect?
Compaction
Ease of tillage
Drainage
Water-holding capacity

24. What are three major constituents of mineral soil?
Sand mm
Silt mm
Clay- less than .002 mm

25. Soil Permeability
The ability of soil to allow water to percolate or move through the soil
This is impacted by soil size and WHC like sand, silt, or clay

26. Properties
50% solid
50% pore space
25% water
25%air

27. Soil Triangle

28. pH
Ideal for most ornamental plants and lawn or turf grasses is

29. Changing pH To make a soil more acidic, lower pH Add sulfur
Sulfur is acidic and will lower the pH

30. Changing pH To make a soil more alkaline (basic), increase pH Add lime
Lime is alkaline will increase the pH

31. Pedology The study of soils A pedologist is a soil scientist
Study soil science at a land grant university like NCSU or NC A & T

32. Taking Soil Samples
Purpose-determine need for lime, nitrogen, phosphorus, and potassium
Nutrient deficiencies determined
Sent to specialized labs to determine drainage, contamination, insects, diseases

33. When to take a soil sample…
Anytime
Early enough to allow adequate time to implement lab recommendations
Fall planting-take in spring
Spring planting-take in fall

34. Procedures 1. Get soil sample information sheets and cartons.
2. Clean tools and containers.
3. Take one composite sample from each uniform area.
4. Take small cores or slices from the large uniform area.

35. Procedures-continued
5. Take core of slices about 4”deep for lawns and 6”deep for fields
6. Mix the cores or slices together in a clean bucket and take a sample of about one pint

36. Procedures-continued
7. Complete the sample information sheet and carton information.
8. Draw a map and keep a record of where you sampled and sample numbers.
9. Include the info sheet with the carton and mail or take to lab

37. Interpretation of Soil Test Reports
Report provides the results of analysis and suggests a fertilization program, lime application, and other treatments

38. Interpretation
Actual nutrients available are reported in ppm and also in levels such as high, low, very low,very high, slightly acid to help the grower understand the report.

39. Interpretation The level of acidity or alkalinity is shown by the pH.
7.2 slightly alkaline
7.0 neutral
6.3 moderately acidic

40. Interpretation
Need more help? Contact your local cooperative extension agent, agricultural education teacher or other knowledgeable people who work with soil test reports.

41. Erosion When water or wind takes particles of soil and moves them away
This often leads to pollution
Detrimental to the environment

42. Soil Conservation
The practice of keeping or improving soil in an area

43. Soil Erosion and Conservation at WHS
Now, let’s go see where we have erosion and we will figure out what we can do to solve the problem.