This paper presents a five-year study monitoring cotton bollworm (Helicoverpa armigera) flight dynamics using pheromonal traps and a study relating to the behavior of nine maize hybrids from two maturity groups in response to a pest attack in 2024. The monitoring and field assessments were conducted in Southeast Romania, Călărași County, at the NARDI Fundulea. During the monitoring period, from 2020 to 2024, air temperature was higher than average in the summer months while rainfall was below average, except in June 2021. The total number of moths captured in the traps was 246 in 2020, 406 in 2021, 5064 in 2022, 1024 in 2023, and 4145 in 2024. In the middle of July 2022, the average captured moths per trap was 483.3; in the middle of September, it was 589.0 catches. In 2024, in the last 10 days of July, the average captured moths per trap was 311.7; in the last 10 days of August, it was 358.0, while in the middle of September, it was 362.3. In 2024, at the beginning of August, the attack incidence of corn earworm on maize hybrids ranged from 43.75 to 53.75%, and on 13 September, it was 100% for all hybrids. This is the first report from southeast Romania that mentions a higher population of cotton bollworm in the late summer and beginning of autumn and the first report to mention a large number of pest attacks on maize cobs in September.

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.