The hypothesis that host-plant selection by the alticine flea beetle,Agasicles hygrophilaSelman and Vogt, may be influenced by the nutritive properties of alligatorweed was investigated. Alligatorweed deficient in phosphorus, calcium, and magnesium and plants receiving complete nutrition were used to study flea beetle attraction, feeding, and fecundity. Plants receiving complete nutrition were almost always preferred in feeding and fecundity tests to mineral-deficient plants. All responses were significant except fecundity in the minus-magnesium group and a choice test on attraction in the calcium group. The ratio of leaf tissue consumed per egg produced by the female was the same in both control and experimental groups.