Surveys from 1965 to 1977 of the native wild and introduced naturalized flora of the delta of Mississippi for F1generation larvae of the overwintered population ofHeliothis zea(Boddie) andH. virescens(F.) showed thatH. zealarvae occurred at least 1 week earlier thanH. virescenslarvae. Eight plant species supported populations of bothHeliothisspecies. Both crimson clover andGeranium dissectumL. were major hosts ofH. zea. Although brief high populations ofH. virescensoccurred on several plant species,G. dissectumwas the only early-season host that supported high populations ofH. virescensover an extended period of time.