Egg - Nearly spherical and about 1 mm in diameter, the translucent egg has a slightly greenish tint.
Larva - The first instar of the sweetpotato hornworm has a white body and a black anal horn. Later instars are basically green or brown with prominent, slanted black markings on each side of the body and a black anal horn. The head is also green or brown with 3 dark stripes on each side. A fifth instar hornworm may be 90 mm or more in length.
Pupa - The reddish-brown pupa is about 15 mm wide and 64 mm long. The large tongue case has a pitcher-handle-like appearance.
Host Plants - Sweetpotato and morning glory are the primary food plants of this hornworm although jimsonweed has also been reported as a host.
Damage - These large worms consume much foliage leaving only bare stems and petioles on plants. Sweetpotato hornworms have been reported to display armyworm-like habits in Florida; however, their movement in large groups has not been observed here in North Carolina. Larvae often hide under large leaves at the base of plants.
Life History - The biology of this pest is not well documented. Its life history is probably very similar to that of tomato and tobacco hornworms (see TOMATO: Hornworms). Moths appear in early June, again in August and September, and once more in early fall. There are probably 2-1/2 generations per year.
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