During 2 years of field experiments, five crops showed consistent differences in their response to the seedcorn maggot,Delia platura(Meigen). Watermelons and cantaloupes showed greatest stand losses, snap and lima beans were intermediate, and sweet corn appeared to be unaffected despite a seed infestation level of at least 50%. More than twice as many seedcorn maggot larvae and pupae were collected from lima beans than from the melon crops. The smallest number of larvae and pupae were taken from plots where no seeds were planted. In these plots seedcorn maggots that were present either immigrated before pupation or developed on organic soil debris and weed seeds. In 1982 the bean and corn plots produced heavier pupae than the melon plots. Thus, seedcorn maggot populations may build up more rapidly in bean and corn crop areas than in those planted with melons, although stand loss may be more evident in the latter.