At Vir-Clar Farm in Fond du Lac, Wis., co-owner and calf manager Katie Grinstead uses a system of colored duct tape to communicate with calf feeders. Different colored duct tape attached to each calf hutch is used to differentiate the amount of milk a calf receives. For example, calves with purple duct tape receive 2 gallons of pasteurized milk, while those with green duct tape receive three-fourths of a pail.
