none not entered The effect of seed predators on seed production of turtlehead (Chelone obliqua : Scrophulariaceae) was examined. Larval seed predators (Endothenia hebesana : Tortricidae and Phytomyza cheloniae : Agromyzidae) reduced seed production by 21%. Half of the reproductive stalks supported larval seed predators, with 24% of the seed capsules attacked. Stalks available generally and those used by the parasitoids were similar in terms of number of seed capsules and size of capsules. Presence of tortricid hosts was highly correlated with number of capsules perstalk. The parasitoids (Agathis sp. and Macrocentrus sp.: Braconidae) were selective in choosing capsuled stalks, but occasionally they chose and even probed stalks without tortricid hosts. This is a system where seed production often is reduced due to severe herbivory by specialist folivores.