Page 1 of 54
ISA Arborist Certification Exam 1 & 2 ALL 250
QUESTIONS AND DETAILED SOLUTIONS LATEST
UPDATE THIS YEAR
ISA Arborist Certification Exam 1
QUESTION: What soil horizon category is most likely to include a large amount of organic
material?
(A) A
(B) E
(C) B
(D) C - ANSWER-A
QUESTION: What soil below most likely has the highest infiltration rate?
(A) Loose sand
(B) Compacted silt
(C) Loose silt
(D) Compacted clay - ANSWER-A
QUESTION: What substance may be added to soil to temporarily lower the PH?
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,Page 2 of 54
(A) Lime
(B) Ash
(C) Sulfur
(D) Calcium - ANSWER-C
Q; For an ideal soil ratio, what component takes up the least amount of space within the overall
makeup of the soil structure?
(A) Water
(B) Air
(C) Organic matter
(D) Mineral-rich soil - ANSWER-C
QUESTION: What is the correct scientific name for the sugar maple genus?
(A) Picea(B) Ulmus (C) Magnolia (D) Acer - ANSWER-D
QUESTION: What statement regarding the net charge of soils is true?
(A) Soils have a net negative charge
(B) Soils have a net positive charge
(C) Positive sites outnumber negative sites
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,Page 3 of 54
(D) Soils have only entirely positive or negative sites - ANSWER-A
QUESTION: A soil structure has a layer of clay above a layer of sand. At what point will water
begin to enter the lower layer of sand?
(A) The water will flow immediately through the clay layer into the sand layer
(B) After the clay layer is partially saturated
(C) After the clay layer is fully saturated
(D) The sand layer is impervious - ANSWER-C
QUESTION: What soil moisture condition occurs when both the micro and macropores are filled
with water?
(A) Pore capacity (B) Wilting point (C) Field capacity (D) Saturation - ANSWER-D
QUESTION: What irrigation system type is best suited for use on deeper, more mature root
systems?
(A) Drip irrigation
(B) High-pressure injection
(C) Basin irrigation
(D) Soaker hose - ANSWER-B
3
, Page 4 of 54
QUESTION: What tree species is commonly identified as having leaves in an opposite
arrangement?
(A) Hawthorne (B) Ash(C) Sycamore (D) Oak - ANSWER-B
QUESTION: A soil with a high buffering capacity will have which of the following characteristics?
(A) High percentage of pore space
(B) Easily compacted
(C) High retention of water
(D) Resistant to changes in PH levels - ANSWER-D
QUESTION: In relation to the frequency of irrigation, what statement below is true regarding
the differences between sandy or clay soils?
(A) Sandy soils need to be irrigated more frequently and for shorter periods than clay
(B) Sandy soils need to be irrigated more frequently and for longer periods than clay
(C) Sandy soils need to be irrigated less frequently and for shorter periods than clay
(D) Sandy soils need to be irrigated less frequently and for longer periods than clay - ANSWER-A
QUESTION: The movement of water within the soil defines which of the following?
(A) Infiltration (B) Percolation (C) Transpiration (D) Desiccation - ANSWER-B
4
ISA Arborist Certification Exam 1 & 2 ALL 250
QUESTIONS AND DETAILED SOLUTIONS LATEST
UPDATE THIS YEAR
ISA Arborist Certification Exam 1
QUESTION: What soil horizon category is most likely to include a large amount of organic
material?
(A) A
(B) E
(C) B
(D) C - ANSWER-A
QUESTION: What soil below most likely has the highest infiltration rate?
(A) Loose sand
(B) Compacted silt
(C) Loose silt
(D) Compacted clay - ANSWER-A
QUESTION: What substance may be added to soil to temporarily lower the PH?
1
,Page 2 of 54
(A) Lime
(B) Ash
(C) Sulfur
(D) Calcium - ANSWER-C
Q; For an ideal soil ratio, what component takes up the least amount of space within the overall
makeup of the soil structure?
(A) Water
(B) Air
(C) Organic matter
(D) Mineral-rich soil - ANSWER-C
QUESTION: What is the correct scientific name for the sugar maple genus?
(A) Picea(B) Ulmus (C) Magnolia (D) Acer - ANSWER-D
QUESTION: What statement regarding the net charge of soils is true?
(A) Soils have a net negative charge
(B) Soils have a net positive charge
(C) Positive sites outnumber negative sites
2
,Page 3 of 54
(D) Soils have only entirely positive or negative sites - ANSWER-A
QUESTION: A soil structure has a layer of clay above a layer of sand. At what point will water
begin to enter the lower layer of sand?
(A) The water will flow immediately through the clay layer into the sand layer
(B) After the clay layer is partially saturated
(C) After the clay layer is fully saturated
(D) The sand layer is impervious - ANSWER-C
QUESTION: What soil moisture condition occurs when both the micro and macropores are filled
with water?
(A) Pore capacity (B) Wilting point (C) Field capacity (D) Saturation - ANSWER-D
QUESTION: What irrigation system type is best suited for use on deeper, more mature root
systems?
(A) Drip irrigation
(B) High-pressure injection
(C) Basin irrigation
(D) Soaker hose - ANSWER-B
3
, Page 4 of 54
QUESTION: What tree species is commonly identified as having leaves in an opposite
arrangement?
(A) Hawthorne (B) Ash(C) Sycamore (D) Oak - ANSWER-B
QUESTION: A soil with a high buffering capacity will have which of the following characteristics?
(A) High percentage of pore space
(B) Easily compacted
(C) High retention of water
(D) Resistant to changes in PH levels - ANSWER-D
QUESTION: In relation to the frequency of irrigation, what statement below is true regarding
the differences between sandy or clay soils?
(A) Sandy soils need to be irrigated more frequently and for shorter periods than clay
(B) Sandy soils need to be irrigated more frequently and for longer periods than clay
(C) Sandy soils need to be irrigated less frequently and for shorter periods than clay
(D) Sandy soils need to be irrigated less frequently and for longer periods than clay - ANSWER-A
QUESTION: The movement of water within the soil defines which of the following?
(A) Infiltration (B) Percolation (C) Transpiration (D) Desiccation - ANSWER-B
4
