Digenetic trematodes (class Trematoda) often plague pond-reared fishes. Most digenetic trematodes are not a serious threat to fish health; however, their mere presence often renders the fish undesirable by consumers. The black grub (Uvulifer ambloplitis), white grub (Posthodiplostomum minimum), and yellow grub (Clinostomum complanatum) are commonly seen digenetic trematodes in fish in earthen ponds located in the North Central Region of the United States. The purpose of this publication is to discuss the biology and prevention of these parasites, along with their effect on infected fish. Hereafter, these digenetic trematodes will be referred to as “grubs”.