CR-21 Landscapes and Irrigation AZROC
Test Prep EXAM, QUESTIONS WITH
Verified Correct ANSWERS | 2026 Latest
update
What is the minimum thickness of brick for the exterior wall of a fireplace?
a) 6 inches
b) 8 inches
c) 10 inches
d) 9 inches - correct answer8 Inches
What is 1/2 inch of accumulated organic material in a grassy area called?
a) mulch
b) ground cover
c) stolons
d) thatch layer - correct answerThatch Layer
What should be provided as a cover for the drain tile before installing the pond liner
where subdrain is used?
a) 4 inches of pea gravel
b) screen with 1/4 inch mesh
c) a pool grate
d) 8 inches of medium sized rock - correct answer4 inches of pea gravel
How do you properly plant ground cover?
a) in a circular pattern
b) in rows, each row staggered
c) in groups of 2
d) 18 inches apart in rows - correct answerIn rows, each row staggered
You are going to pour a concrete pad that is 16 feet by 22 feet and 4 inches thick, how
many cubic yards of concrete are needed?
a) 7.3
,b) 6.3
c) 3.3
d) 4.3 - correct answer4.3 cubic yards
4.3 cubic yards
4inches ---> 0.333ft
Cubic feet to cubic yards /27
16*22*0.333=117.3333
117.3333/27 = 4.3 cubic yards
How wide should the footer be for a CMU wall?
a) equal to the width of the block
b) equal to the depth of the frostline
c) three times the width of the block
d) twice the width of the block - correct answerTwice the width of the block
How does a contractor know how to fill a trench to a certain grade?
a) by guessing
b) the type of soil
c) by available backfill
d) the specifications - correct answerThe specifications
How many 8inch x 8inchx16inch concrete masonry blocks will be required for a wall that
is 8 feet 8 inches high and 104 feet long?
a) 936
b) 1088
c) 1124
d) 1014 - correct answer1014 blocks
8 feet * 12 inches = 96 inches + 8 inches = 104 inches
104 inches / 8 inches = 13 for height
104 feet * 12 inches = 1248 inches
1248 inches / 16 inches = 78 for length
13 * 78 = 1014 blocks
What is the maximum height above grade of a wooden deck that a CR-21 license may
build?
a) 36 inches
b) 48 inches
c) 18 inches
d) 29 inches - correct answer29 inches
,How do you choose a weir?
a) by the cost
b) without calculations, it is better to go with a bigger weir
c) without calculations, it is better to go with a smaller weir
d) by the material used - correct answerWithout calculations, it is better to go with a
bigger weir
How high can a segmented wall be built?
a) 3 feet
b) 6 feet
c) 9 feet
d) 4 feet - correct answer4 feet
Which is the most common voltage requirement for the operation of a typical irrigation
system remote control valve?
a) 24 volt DC
b) 12 volt DC
c) 12 volt AC
d) 24 volt AC - correct answer24 volt AC
All of the following are reasons for pruning plants except to:
a) restricted size
b) rejuvenate growth
c) decrease fruit bearing capacity
d) improve flowering - correct answerDecrease fruit bearing capacity
What type of tree would make a good focal point and screen?
a) wide oval shaped
b) pyramidal
c) spreading
d) vase shaped - correct answerWide oval Shaped
What is necessary to supply power to the electrical source on a water fixture?
a) 12-3 wire
b) flexible conduit
c) 3 phase motor
d) schedule 40 conduit - correct answerSchedule 40 conduit
, What fitting is used for changing directions with a pipe vertically or horizontally?
a) reducing 90 degree threaded elbow
b) 90 degree slip elbow
c) 90 degree threaded elbow
d) reducing 90 degree slip elbow - correct answer90 degree slip elbow
Which of the following should NEVER be done when transplanting a Balled and
Burlapped (B&B) evergreen?
a) loosen the burlap around the soil ball
b) water deeply when the hole is half full
c) dig the hole 100 percent larger than the soil ball
d) apply fertilizer to the soil during conditioning - correct answerApply fertilizer to the soil
during conditioning
What is the minimum distance that a portable heater should be placed away from a
wall?
a) 24 inches
b) 12 inches
c) 18 inches
d) 36 inches - correct answer12 inches
What side of a cactus develops a thicker tougher skin due to sun exposure?
a) east side
b) west side
c) south side
d) north side - correct answerSouth side
If pouring concrete and the ground is frozen (or, when the temperature is freezing), what
do you do?
a) O.K to pour once the ground is wet
b) O.K if you cover with straw afterwards
c) is common practice during cold
d) absolutely no pour - correct answerAbsolutely no pour
Pavers should be laid?
a) after grading
b) after soil preparation
Test Prep EXAM, QUESTIONS WITH
Verified Correct ANSWERS | 2026 Latest
update
What is the minimum thickness of brick for the exterior wall of a fireplace?
a) 6 inches
b) 8 inches
c) 10 inches
d) 9 inches - correct answer8 Inches
What is 1/2 inch of accumulated organic material in a grassy area called?
a) mulch
b) ground cover
c) stolons
d) thatch layer - correct answerThatch Layer
What should be provided as a cover for the drain tile before installing the pond liner
where subdrain is used?
a) 4 inches of pea gravel
b) screen with 1/4 inch mesh
c) a pool grate
d) 8 inches of medium sized rock - correct answer4 inches of pea gravel
How do you properly plant ground cover?
a) in a circular pattern
b) in rows, each row staggered
c) in groups of 2
d) 18 inches apart in rows - correct answerIn rows, each row staggered
You are going to pour a concrete pad that is 16 feet by 22 feet and 4 inches thick, how
many cubic yards of concrete are needed?
a) 7.3
,b) 6.3
c) 3.3
d) 4.3 - correct answer4.3 cubic yards
4.3 cubic yards
4inches ---> 0.333ft
Cubic feet to cubic yards /27
16*22*0.333=117.3333
117.3333/27 = 4.3 cubic yards
How wide should the footer be for a CMU wall?
a) equal to the width of the block
b) equal to the depth of the frostline
c) three times the width of the block
d) twice the width of the block - correct answerTwice the width of the block
How does a contractor know how to fill a trench to a certain grade?
a) by guessing
b) the type of soil
c) by available backfill
d) the specifications - correct answerThe specifications
How many 8inch x 8inchx16inch concrete masonry blocks will be required for a wall that
is 8 feet 8 inches high and 104 feet long?
a) 936
b) 1088
c) 1124
d) 1014 - correct answer1014 blocks
8 feet * 12 inches = 96 inches + 8 inches = 104 inches
104 inches / 8 inches = 13 for height
104 feet * 12 inches = 1248 inches
1248 inches / 16 inches = 78 for length
13 * 78 = 1014 blocks
What is the maximum height above grade of a wooden deck that a CR-21 license may
build?
a) 36 inches
b) 48 inches
c) 18 inches
d) 29 inches - correct answer29 inches
,How do you choose a weir?
a) by the cost
b) without calculations, it is better to go with a bigger weir
c) without calculations, it is better to go with a smaller weir
d) by the material used - correct answerWithout calculations, it is better to go with a
bigger weir
How high can a segmented wall be built?
a) 3 feet
b) 6 feet
c) 9 feet
d) 4 feet - correct answer4 feet
Which is the most common voltage requirement for the operation of a typical irrigation
system remote control valve?
a) 24 volt DC
b) 12 volt DC
c) 12 volt AC
d) 24 volt AC - correct answer24 volt AC
All of the following are reasons for pruning plants except to:
a) restricted size
b) rejuvenate growth
c) decrease fruit bearing capacity
d) improve flowering - correct answerDecrease fruit bearing capacity
What type of tree would make a good focal point and screen?
a) wide oval shaped
b) pyramidal
c) spreading
d) vase shaped - correct answerWide oval Shaped
What is necessary to supply power to the electrical source on a water fixture?
a) 12-3 wire
b) flexible conduit
c) 3 phase motor
d) schedule 40 conduit - correct answerSchedule 40 conduit
, What fitting is used for changing directions with a pipe vertically or horizontally?
a) reducing 90 degree threaded elbow
b) 90 degree slip elbow
c) 90 degree threaded elbow
d) reducing 90 degree slip elbow - correct answer90 degree slip elbow
Which of the following should NEVER be done when transplanting a Balled and
Burlapped (B&B) evergreen?
a) loosen the burlap around the soil ball
b) water deeply when the hole is half full
c) dig the hole 100 percent larger than the soil ball
d) apply fertilizer to the soil during conditioning - correct answerApply fertilizer to the soil
during conditioning
What is the minimum distance that a portable heater should be placed away from a
wall?
a) 24 inches
b) 12 inches
c) 18 inches
d) 36 inches - correct answer12 inches
What side of a cactus develops a thicker tougher skin due to sun exposure?
a) east side
b) west side
c) south side
d) north side - correct answerSouth side
If pouring concrete and the ground is frozen (or, when the temperature is freezing), what
do you do?
a) O.K to pour once the ground is wet
b) O.K if you cover with straw afterwards
c) is common practice during cold
d) absolutely no pour - correct answerAbsolutely no pour
Pavers should be laid?
a) after grading
b) after soil preparation
