Adult two-lined chestnut borers are slender, black beetles with a bluish to
greenish hue that are 1/5-1/2 inch (5-13 mm) long with two faint, yellowish
stripes along their back. Larvae are legless, white, slender, and about 1 inch (2.5 cm) long when fully grown with two spines at the tip of the abdomen and have an enlarged, flattened front end, characteristic of the Buprestidae.