CPA Pest Identification and Management 3 — Questions and Answers
Question 1: A lawn exhibits irregular dead patches with grass roots severed at soil level. The most likely culprit is:
- White grub (scarab larvae) (Correct answer)
- Sod webworm
- Chinch bug
- Billbug adult
Correct answer: White grub (scarab larvae)
White grubs feed on turfgrass roots below the soil surface, severing them and creating irregular dead patches that can be lifted like loose carpet.
Question 2: Fire ant mounds are typically found in which type of location?
- Open, sunny areas such as lawns, fields, and roadsides (Correct answer)
- Dense shaded forest understory
- Submerged or waterlogged soils
- Inside walls of heated buildings
Correct answer: Open, sunny areas such as lawns, fields, and roadsides
Red imported fire ants prefer open, warm, sunny environments and build mounds in turf, pastures, roadsides, and gardens.
Question 3: Which of the following correctly describes the damage caused by thrips on ornamental plants?
- Silver-streaked or bronzed foliage with tiny black fecal specks (Correct answer)
- Large irregular holes chewed through leaves
- Galls or deformations on stems caused by egg-laying
- White powdery coating on leaf surfaces
Correct answer: Silver-streaked or bronzed foliage with tiny black fecal specks
Thrips rasp and suck plant cells leaving a characteristic silvery-bronze stippling and tiny dark fecal deposits on foliage and petals.
Question 4: The grape berry moth overwinters primarily as:
- Pupae in cocoons under loose bark or leaf litter (Correct answer)
- Eggs on grape canes
- Larvae inside berries left on the vine
- Adults in soil debris
Correct answer: Pupae in cocoons under loose bark or leaf litter
Grape berry moth overwinters as pupae in silken cocoons tucked under loose bark, in crevices, or in leaf litter on the vineyard floor.
Question 5: Which tool is BEST suited for accurately counting small, mobile insects like aphids on leaf samples in the field?
- 10x hand lens or jeweler's loupe (Correct answer)
- Sweep net
- Berlese funnel
- Pitfall trap
Correct answer: 10x hand lens or jeweler's loupe
A 10x hand lens allows close examination of leaf samples to accurately count and identify small insects like aphids in the field.
Question 6: In a degree-day model for insect pest management, what is the base temperature?
- The minimum temperature below which pest development stops (Correct answer)
- The average daily temperature used for forecasting
- The lethal temperature that kills the pest
- The optimum temperature for maximum pest reproduction
Correct answer: The minimum temperature below which pest development stops
The base temperature is the lower developmental threshold — the temperature below which a pest ceases to develop or accumulate heat units.
Question 7: When inspecting stored grain for pest activity, which sign most strongly indicates an active weevil infestation?
- Round exit holes in kernels and fine flour-like frass (Correct answer)
- Webbing between kernels near the surface
- Small moths flying near the grain bin entrance
- White cottony masses on grain surfaces
Correct answer: Round exit holes in kernels and fine flour-like frass
Grain weevils develop inside kernels, and adult emergence creates characteristic round exit holes with fine powdery frass indicating an active, internal infestation.
CPA Pest Identification and Management 3
A lawn exhibits irregular dead patches with grass roots severed at soil level.
The most likely culprit is: