Generalized description of the codling moth's seasonal development. Moth flights and developmental times vary with temperatures and location. Designated are: (OW) overwintered population, (1) first generation, (2) second generation, (3) third generation. A portion of the second generation larvae enter diapause and become part of the overwintering larval population, except in very warm locations. In these locations, most of the second generation completes development, and in some years a partial fourth (4) generation occurs.

Illustration from Integrated Pest Management for Apples and Pears. UC ANR Publication 3340.