We evaluated the flight behavior of E. giganteana in response to semiochemicals identified from other closely related Eucosma species, including: (Z)- and (E)-8-dodecenyl acetate, (E)-9-dodecenyl acetate, (Z)-8-dodecenol, (E,E)-8,10-dodecadienyl acetate, and (Z,E)-9,12-tetradecadienyl acetate. The goals of this study were to evaluate whether any of these compounds could improve capture of E. giganteana on clear sticky cards in the field, and whether the most attractive volatiles might affect flight behavior on a computer-automated flight mill assay. We found that there was significant attraction to (E)-8-dodecenyl acetate in two years in the field, which may possibly be a component in the pheromone blend for E. giganteana. On flight mills, E. giganteana flew an average of 23 km in a 24 h period. The presence of attractive stimuli (e.g., (E)-8-dodecenyl acetate) had arresting properties and decreasing flight distance on the mill by 78 to 80%. The longest flight distances were registered in the morning (4:00–12:00) and were 1.8-fold greater than flight distances and durations at night (20:00–4:00). (E)-8-dodecenyl acetate may be useful in behaviorally based monitoring and management strategies for E. giganteana. Overall, our research expands the knowledge on the chemical ecology of adult E. giganteana. Dataset includes testing field-captured E. giganteana adults collected from UV light traps deployed at The Land Institute in Salina, KS, and hand-collected at night during the period of peak activity for E. giganteana. Two trials are included: a field baiting assay, and laboratory flight mill assay. In the field baiting assay, each field had three transects spaced at least 10 m apart, each with a full set of semiochemical treatments represented. Each trap within the transect was spaced 10 m apart. Each trap consisted of a 1.27-cm diameter PVC pipe hammered in row with the silflower to a finished height of 1 m, in line with the canopy of Silphium integrifolium. A single 30.4 cm × 30.4 cm clear sticky card (Alpha Scents, Canby, OR, USA) was folded in half and inserted in a 271 cm long sticky card ring holder (Olson Products Inc., Medina, OH, USA). The ring holder was bent at a 90° angle to wedge the card holder upright in position, which was subsequently wedged in the opening at the top of the PVC pipe. A single, capped LDPE 3-mL dropping bottle with one of the semiochemical treatments above was inserted in the top of the PCV pipe opening and affixed in place by tying it to the card holder with garden wire. Every week, the lures were replaced with a freshly prepared treatment and the position of the lure was rotated in the transect every two weeks. Traps were rotated because of the short duration of the flying season and resulted in every treatment occupying every position at least once. Sticky cards were changed on a weekly basis after the first recorded capture of an E. giganteana adult. Traps were deployed 7 June 2019 to 14 August 2019 and 15 June 2020 to 10 August 2020. In total, there were n = 3 replicates of each semiochemical treatment per field site. The number of E. giganteana and Lepidopteran nontargets was counted on each sticky card after freezing cards at −20 °C for at least 24 h. For the flight mill assay, six adults were run simultaneously on the six flight mills described in the associated article (15-FMASM SDP Unit, Crist Instrument Co., Hagerstown, MD, USA) to test flight capacity. Each trial was started between 15:00 and 18:00 by gently blowing on the insect to initiate flight and run for 24 h in parallel. Assays were conducted at 21.4 ± 0.01 °C temperature and 54.2 ± 0.2% RH and monitored with a datalogger (UX100-011, Hobo, temp/RH logger, Onset, Bourne, MA, USA). The semiochemical treatments in the flight mill assay included (E)-8-dodecenyl acetate, (Z)-9-dodecenyl acetate, and an unbaited control (acetone solvent only). Semiochemicals were freshly prepared in LDPE dropping bottles, as in the field-baiting experiment (as above), and placed in the center among the flight mills on a nonporous glass surface to prevent contamination. There were 12–18 replicates per treatment. At the end of a trial, insects were detached and weighed on a balance. Data were streamed in real time to a computer which automatically record the flight parameters: distance flown, the number of tandem flight bouts over the sampling interval (flights lasting more than 1 s), mean flight bout duration, and mean distance flown per bout. Data were also parsed by time of date to determine maximum time of dispersal. Data were analyzed with R software. See file list for descriptions of each data file. Resources in this dataset:Resource Title: Field Baited Sticky Card Assay. File Name: eucosma_sticky_card_captures_raw_data_2019_2020.csvResource Software Recommended: Excel,url: https://www.microsoft.com/en-us/microsoft-365/excel Resource Title: Flight Mill Assay - 24 h period . File Name: flight_mill_data_full_day_eucosma.csvResource Software Recommended: Excel,url: https://www.microsoft.com/en-us/microsoft-365/excel Resource Title: Flight Mill Assay - Diurnal Time Course. File Name: flight_mill_data_period_diurnal_eucosma.csvResource Software Recommended: Excel,url: https://www.microsoft.com/en-us/microsoft-365/excel Resource Title: README file list. File Name: file_list_Eucosma_semiochemicals.txt