Adult black cutworm has a body length of 18 ~ 28 mm, wings spread 40 ~ 54 mm, oval, slightly raised top, flat bottom and inconspicuous egg hole. Eggs are milky white at first birth and gradually turn brown before hatching. Larvae is grayish brown at first hatching, yellowish green before the third instar, and gradually turns grayish brown after the third instar. See Table 2 for the larval morphology of the black cutworm.
Larvae of cutworm often appears in the field with cutworm and cutworm, which are very similar and easy to be confused. The main characteristics of the three are compared as follows, which is easy to identify.
Key list of three kinds of ground tiger larvae;
1. Black cutworm: The body surface is rough and densely covered with particles of different sizes. The wig of D 1 is obviously smaller than that of D2.
2. Yellow cutworm: The body surface has no particles of different sizes, smooth or densely wrinkled, and there are two large yellow-brown spots on the hip plate, with a broken center and a body length of 4 1-60mm.
3. The hip plate of the soil tiger is almost a whole black spot with wrinkles and turtle cracks.