Flight Dynamics of the True Armyworm (Mythimna unipuncta) in a Maize Agroecosystem in Southeast Romania

True armyworm (Mythimna unipuncta) is a polyphagous pest that damages forage grasses, small grains, or maize crops. This pest is found in the Americas, Western Africa, Asia, and Europe. The true armyworm was detected in Romania a few decades ago, but no studies have examined its flight dynamics in crops. This paper presents five years of results from monitoring the flight dynamics of the true armyworm (Mythimna unipuncta) using pheromone traps, and two years of field assessments for larvae scouting at maize plants. The field site is in southeastern Romania, in Călărași County, at the National Agricultural Research and Development Institute in Fundulea, within a temperate continental climate. Five moths were captured in the traps in 2021; 18 moths were captured in 2022; 32 in 2023; 38 in 2024, and 22 moths were captured in 2025. In 2021, the true armyworm flight started on 21 September and ended on 27 October; in 2022, the flight started on 31 October and ended on 25 November; in 2023, the flight started on 23 October and ended on 22 November; in 2024 the flight started on 8 October and ended on 28 November; while in 2025 the flight started on 3 October and ended on 25 November. Results from maize plant assessments for true armyworm larval scouting indicate that no larvae were detected in the last twenty days of July during 2024 and 2025, August, and the first ten days of September. This is the first report in the Romanian literature concerning the constant presence of the true armyworm during autumn in the southeast of this country over the last five years. However, the pest population density in this country did not reach pest levels, but this situation could change in the future due to global warming.