This dataset is related to the study: " Seed management and selection in old maize landraces from the French Pyrenees: ethnobotanical survey and selection experiment" by Gouesnard et al. (submitted in 2025). We asked old farmers who had cultivated maize populations to select 15 ears from 150 exposed ears. Four maize populations were included in the study. The data include the description of the 150 ears shown to the old farmers and of the 15 ears selected by each of them, as well as the dataset for estimating the narrow sense heritability of ear morphological traits, based on a full-sib half-sib design. All files were used to estimate the expected genetic change after one generation of mass selection using the farmers’ selection criteria.