After cutting the exit hole, the larva retreats a short distance into its tunnel and pupates.

It breaks the skin surface left by the larva by force and leaves the exit hole.

Full-grown larva cut an exit hole in the stem, leaving only a thin layer of epidermis to cover the exit hole.

In fall, they cut a circular exit hole at the base where pupation takes place.

After completion of the exit hole it spins a cocoon within the seed, with a passage way leading to the door.