WISCONSIN PESTICIDE APPLICATOR PRACTICE
TEST – CATEGORY 6.0 AQUATIC 2025
180-minute • 100 scored items • 4-option multiple
choice • Adobe Devanagari key
Question 1
A 12-acre lake averages 6 ft depth. The volume in acre-feet is:
A. 18 ac-ft
B. 36 ac-ft
C. 72 ac-ft
D. 144 ac-ft
Answer: C. 72 ac-ft
Solution: Volume = area × depth = 12 ac × 6 ft = 72 ac-ft; basic DATCP math expectation.
Question 2
A copper-based algicide label prohibits use when total alkalinity is <50 ppm. The
restriction primarily protects:
A. Human swimmers from skin irritation
B. Fish from copper toxicity in soft water
C. Irrigation pumps from corrosion
D. Potable water from taste changes
Answer: B. Fish from copper toxicity in soft water
Solution: Low alkalinity = higher soluble Cu²⁺ → greater gill uptake and fish kills; label
is environmental, not human-health.
Question 3
The first principle of IPM for aquatic sites is:
A. Curative chemical treatment
B. Prevention of pest introduction
C. Maximum label rate application
D. Post-treatment fertilisation
Answer: B. Prevention of pest introduction
Solution: WI Extension IPM pyramid places prevention (clean boats, inspect
equipment) before any control tactic.
pg. 1
,Question 4
Commercial aquatic application records must be retained in Wisconsin for:
A. 1 year
B. 2 years
C. 3 years
D. 5 years
Answer: B. 2 years
Solution: ATCP 29.70(2) – 2 years from date of application; 3 years applies to some
other categories, not aquatic.
Question 5
A liquid herbicide rate is 2 fl oz / acre-foot. For 40 ac-ft the product needed is:
A. 20 fl oz
B. 40 fl oz
C. 60 fl oz
D. 80 fl oz
Answer: D. 80 fl oz
Solution: 2 fl oz × 40 ac-ft = 80 fl oz; acre-foot rate is core Cat-6 math.
Question 6
Which algae type appears as planktonic “pea-soup” scum and can produce toxins?
A. Filamentous green algae
B. Blue-green algae (cyanobacteria)
C. Chara
D. Nitella
Answer: B. Blue-green algae (cyanobacteria)
Solution: Cyanobacteria are prokaryotic, buoyant, and associated with microcystin;
filamentous (A) and charophytes (C,D) are non-toxic.
Question 7
The Restricted-Entry Interval (REI) for most copper-based aquatic formulations is:
A. 0 hours when water is not used for irrigation
B. 24 hours for swimming
C. 48 hours for livestock watering
D. Set by the label and must be followed
Answer: D. Set by the label and must be followed
Solution: Aquatic labels list site-specific REIs (often 0–24 h); applicator must follow
most restrictive language.
pg. 2
, Question 8
A contractor accidentally spills 2 gal of undiluted diquat into a driveway drain leading to
a creek. The first required action is:
A. Notify DATCP within 2 hours
B. Begin containment and cleanup
C. Call CHEMTREC
D. Warn downstream users
Answer: B. Begin containment and cleanup
Solution: Immediate containment protects the resource; regulatory notification (A)
follows once imminent danger is addressed.
Question 9
Eurasian watermilfoil is best distinguished from native northern milfoil by:
A. Flower color
B. Number of leaflet pairs per leaf
C. Stem thickness
D. Root length
Answer: B. Number of leaflet pairs per leaf
Solution: EWM typically has ≥12 leaflet pairs vs 5–11 for northern; this is the UW-
Extension field diagnostic.
Question 10
The maximum boom height above water surface when applying aquatic herbicide is
generally:
A. 6 inches
B. 12 inches
C. 24 inches
D. Not specified – use lowest practical
Answer: D. Not specified – use lowest practical
Solution: No federal height for aquatic booms; WI BMP is “as low as practical” to
minimize drift, usually ≤12–18 in.
Question 11
Which parameter must be recorded for every aquatic application?
A. Water temperature at 1 ft depth
B. Total alkalinity value
pg. 3
TEST – CATEGORY 6.0 AQUATIC 2025
180-minute • 100 scored items • 4-option multiple
choice • Adobe Devanagari key
Question 1
A 12-acre lake averages 6 ft depth. The volume in acre-feet is:
A. 18 ac-ft
B. 36 ac-ft
C. 72 ac-ft
D. 144 ac-ft
Answer: C. 72 ac-ft
Solution: Volume = area × depth = 12 ac × 6 ft = 72 ac-ft; basic DATCP math expectation.
Question 2
A copper-based algicide label prohibits use when total alkalinity is <50 ppm. The
restriction primarily protects:
A. Human swimmers from skin irritation
B. Fish from copper toxicity in soft water
C. Irrigation pumps from corrosion
D. Potable water from taste changes
Answer: B. Fish from copper toxicity in soft water
Solution: Low alkalinity = higher soluble Cu²⁺ → greater gill uptake and fish kills; label
is environmental, not human-health.
Question 3
The first principle of IPM for aquatic sites is:
A. Curative chemical treatment
B. Prevention of pest introduction
C. Maximum label rate application
D. Post-treatment fertilisation
Answer: B. Prevention of pest introduction
Solution: WI Extension IPM pyramid places prevention (clean boats, inspect
equipment) before any control tactic.
pg. 1
,Question 4
Commercial aquatic application records must be retained in Wisconsin for:
A. 1 year
B. 2 years
C. 3 years
D. 5 years
Answer: B. 2 years
Solution: ATCP 29.70(2) – 2 years from date of application; 3 years applies to some
other categories, not aquatic.
Question 5
A liquid herbicide rate is 2 fl oz / acre-foot. For 40 ac-ft the product needed is:
A. 20 fl oz
B. 40 fl oz
C. 60 fl oz
D. 80 fl oz
Answer: D. 80 fl oz
Solution: 2 fl oz × 40 ac-ft = 80 fl oz; acre-foot rate is core Cat-6 math.
Question 6
Which algae type appears as planktonic “pea-soup” scum and can produce toxins?
A. Filamentous green algae
B. Blue-green algae (cyanobacteria)
C. Chara
D. Nitella
Answer: B. Blue-green algae (cyanobacteria)
Solution: Cyanobacteria are prokaryotic, buoyant, and associated with microcystin;
filamentous (A) and charophytes (C,D) are non-toxic.
Question 7
The Restricted-Entry Interval (REI) for most copper-based aquatic formulations is:
A. 0 hours when water is not used for irrigation
B. 24 hours for swimming
C. 48 hours for livestock watering
D. Set by the label and must be followed
Answer: D. Set by the label and must be followed
Solution: Aquatic labels list site-specific REIs (often 0–24 h); applicator must follow
most restrictive language.
pg. 2
, Question 8
A contractor accidentally spills 2 gal of undiluted diquat into a driveway drain leading to
a creek. The first required action is:
A. Notify DATCP within 2 hours
B. Begin containment and cleanup
C. Call CHEMTREC
D. Warn downstream users
Answer: B. Begin containment and cleanup
Solution: Immediate containment protects the resource; regulatory notification (A)
follows once imminent danger is addressed.
Question 9
Eurasian watermilfoil is best distinguished from native northern milfoil by:
A. Flower color
B. Number of leaflet pairs per leaf
C. Stem thickness
D. Root length
Answer: B. Number of leaflet pairs per leaf
Solution: EWM typically has ≥12 leaflet pairs vs 5–11 for northern; this is the UW-
Extension field diagnostic.
Question 10
The maximum boom height above water surface when applying aquatic herbicide is
generally:
A. 6 inches
B. 12 inches
C. 24 inches
D. Not specified – use lowest practical
Answer: D. Not specified – use lowest practical
Solution: No federal height for aquatic booms; WI BMP is “as low as practical” to
minimize drift, usually ≤12–18 in.
Question 11
Which parameter must be recorded for every aquatic application?
A. Water temperature at 1 ft depth
B. Total alkalinity value
pg. 3
