Both sexes of the noctuid moths Lacanobia subjuncta (Grote & Robinson), Mamestra configurata Walker (bertha armyworm) and Xestia c-nigrum (L.) (spotted cutworm) are attracted to the combination of acetic acid and 3-methyl-1-butanol (isoamyl alcohol). A controlled-release system for use of this attractant in traps was comprised of separate polypropylene vials for each chemical, with the chemical release rate delimited by a hole in the vial lid. When hole sizes for both acetic acid and 3-methyl-1-butanol were varied together, numbers of all three moth species trapped were greatest with vial hole diameters 1.0–3.0 mm. For all three species, captures of moths also were positively correlated with the ratio of acetic acid to 3-methyl-1-butanol vial hole sizes (acetic acid vial hole size was varied, 3-methyl-1-butanol vial hole size was held constant). Captures of these moths were not correlated with the ratio of 3-methyl-1-butanol/acetic acid vial hole sizes (3-methyl-1-butanol vial hole size varied, acetic acid vial hole size was held constant), over the range of hole sizes tested. Captures of L. subjuncta, M. configurata, and X. c-nigrum in a wet trap were significantly increased by the addition of boric acid to the trap drowning solution (to retard microbial growth and decomposition of specimens). In a comparison of different designs of traps baited with acetic acid and 3-methyl-1-butanol, greatest numbers of all three species were captured in a dry “bucket” trap which moths entered from near the trap top.