Which pest type causes problems only under specific circumstances or certain times?

• A. Occasional pests
• B. Key pests
• C. Secondary pests
• D. Seasonal pests

Answer: (A)

Pests that cause problems only under specific circumstances or certain times are called occasional pests. The key idea is irregularity: they aren’t a constant threat year after year, but can become problematic when particular factors align—such as unusual weather, crop stress, or a lapse in natural predator populations. Because their impact depends on those conditions, they’re monitored and managed only when those conditions occur, rather than requiring constant control.

If a pest is a constant, predictable threat across many seasons, that’s a sign of a key pest. If a pest isn’t the main offender but can become problematic when primary pest management disrupts natural controls or the crop is stressed, that’s a secondary pest. If a pest is tied primarily to a season and tends to appear every year at that time, that points to seasonal pests.