ISA Arborist Certification Chapter 3 - Soil Science Test
Questions And An- swers A+ Graded!!
1. organic layer 0 Horizon, an unaltered soil, thin layer of decomposing organic matter
2. Loam A mix of three ditterent particle sizes and is often considered an ideal soil
texture because of the favorable characteristics for plant growth.
Not made up of equal mix of sand, silt, clay. Contains less clay
3. Topsoil commonly known as the uppermost layers (O,A,E, and sometimes the
upperpart of B horizon)
4. C Horizon Deepest Soil layer composed of partially weathered parent material.
Soil in this horizon is continually forming.
5. A Horizon Contains most of the fine absorbing roots of trees and is very
biologically active. Rich in organic matter.
6. E Horizon Between the A and B Horizon, lacks the organic matter as in A, has lighter
color due to this.
7. Absorbing RootsRoots found in the upper 6-10 inches of soil
8. Roots Few grow deeper than 3 to 4 ft.
9. Soil Structure Shape, size, strength, and arrangement of soil aggregates form .
10. Micropores Soil pores that retain water and are the source of available water to plants
between rainfalls.
11. Macropores Soil pores too large to hold water against the force of gravity and
become filled with air as water drains from the soil.
12. Bulk Density Mass of dried soil per unit of undisturbed soil volume. Can be used to
assess
whether adequate pore space exists.
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, ISA Arborist Certification Chapter 3 - Soil Science Test
Questions And An- swers A+ Graded!!
13. Sand Soils with a high percentage of are less prone to compaction.
14. Clay Soils with a high percentage of are easily compacted.
15. pH The measure of the acidity or alkalinity of soil.
16. pH 7 pH neutrality
17. pH 0-6.5 Acidic
18. pH 7.5-14 Alkaline
19. pH 6.0 to 6.5 Generally favorable pH for most trees
20. Highly iron, zinc, and manganese may be unavailable. calcium, magnesium, and
Alkaline soils potassi- um may become more available.
21. Highly acidic soils Phosphorus may be unavailable.
22. Micronutrients iron, manganese, ...
23. Temporaliy Add Sulphur
lower pH
24. Raise pH Add Lime
25. Buffering resistance to change in pH, especially in soils high in clay or organic
Capaci- ty matter.
26. Essential
ele- ments Minerals required for tree growth, dissolve in water then become available
for absorption by tree roots
27. ions Essential Elements/ Minerals in solution, are charged particles called
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Questions And An- swers A+ Graded!!
1. organic layer 0 Horizon, an unaltered soil, thin layer of decomposing organic matter
2. Loam A mix of three ditterent particle sizes and is often considered an ideal soil
texture because of the favorable characteristics for plant growth.
Not made up of equal mix of sand, silt, clay. Contains less clay
3. Topsoil commonly known as the uppermost layers (O,A,E, and sometimes the
upperpart of B horizon)
4. C Horizon Deepest Soil layer composed of partially weathered parent material.
Soil in this horizon is continually forming.
5. A Horizon Contains most of the fine absorbing roots of trees and is very
biologically active. Rich in organic matter.
6. E Horizon Between the A and B Horizon, lacks the organic matter as in A, has lighter
color due to this.
7. Absorbing RootsRoots found in the upper 6-10 inches of soil
8. Roots Few grow deeper than 3 to 4 ft.
9. Soil Structure Shape, size, strength, and arrangement of soil aggregates form .
10. Micropores Soil pores that retain water and are the source of available water to plants
between rainfalls.
11. Macropores Soil pores too large to hold water against the force of gravity and
become filled with air as water drains from the soil.
12. Bulk Density Mass of dried soil per unit of undisturbed soil volume. Can be used to
assess
whether adequate pore space exists.
1/
8
, ISA Arborist Certification Chapter 3 - Soil Science Test
Questions And An- swers A+ Graded!!
13. Sand Soils with a high percentage of are less prone to compaction.
14. Clay Soils with a high percentage of are easily compacted.
15. pH The measure of the acidity or alkalinity of soil.
16. pH 7 pH neutrality
17. pH 0-6.5 Acidic
18. pH 7.5-14 Alkaline
19. pH 6.0 to 6.5 Generally favorable pH for most trees
20. Highly iron, zinc, and manganese may be unavailable. calcium, magnesium, and
Alkaline soils potassi- um may become more available.
21. Highly acidic soils Phosphorus may be unavailable.
22. Micronutrients iron, manganese, ...
23. Temporaliy Add Sulphur
lower pH
24. Raise pH Add Lime
25. Buffering resistance to change in pH, especially in soils high in clay or organic
Capaci- ty matter.
26. Essential
ele- ments Minerals required for tree growth, dissolve in water then become available
for absorption by tree roots
27. ions Essential Elements/ Minerals in solution, are charged particles called
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