We decided to title this article with more or less the exact wording of an email we recently received from a reader. She reported that her “catalpa worms have white spikey things all over them,” and she is wondering what is going on. Something is clearly amiss with her Catawba worms. (For the record, Catalpa worms are Catawba worms and vice versa, as the words “Catalpa” and “Catawba” are interchangeable). The reader asked no additional questions, so we will focus only on the white spiky things on the Catalpa worms. We won’t worry about general matters of identification, presuming our reader is definitely dealing with Catawba worms, and we also won’t worry about ways to rectify the problem, which may not be possible anyway.