Question: According to leaf economics spectrum theory, the historic changes in several environmental factors, e.g. land use and nitrogen deposition, are expected to lead to selection of a change in the relative proportion of thin-leaved and thick-leaved plant species. However, it is generally unknown how fast plant communities respond to environmental changes. Location: Denmark. Methods: Time-series analysis of Danish grassland pin-point plant cover data from an eight-year period. Results: Across four grassland habitat types, the cover of thin-leaved plants was found to decrease significantly, but generally only limited trait selection was observed on leaf traits (specific leaf area [SLA] and leaf dry matter content [LDMC]). The mostly negative result may partly be due to the relatively conservative analysis, where the continuous plant trait variables are used for grouping plant species into functional types, which are then treated as dependent variables. This method was chosen in order to account for the sampling process of the vegetation data and is in contrast to most other analyses of trait selection, where it is the community-weighted mean of the traits that is used as the dependent variable. Conclusions: Only limited leaf trait selection was observed in semi-natural grasslands that was not subjected to successional processes.