Classification of pest

A. Based on population:

1. Key pest: Population always above the damage threshold.
2. Occasional pest: Population always remain low and insignificant for long period of time like locust.
3. Potential pest: Might be highly injurious if not kept under control by natural enemies like red spider mite.

B. Based on host range

a. Monophagous pest:

• Confined to single species of plant.
• Eg: Silkworm to mulberry.

b. Oligophagous pest:

• Botanically related plant.
• Eg: Diamond back moth on cruciferous crop.

c. Polyphagous pest:

• Feed on diverse range of plant.

Based on biological characteristics

1. r-pest: High rate of potential increase.
2. K-pest: Low rate of potential increase.
3. r-k pest: Mixture of r and k pest.