Seasonal leaf phenology data for 12 tree species in a cool-temperate deciduous broadleaved forest in Japan from 2005 to 2014

This paper reports seasonal data regarding leaf number, leaf length and width, leaf area, leaf angle, and SPAD (leaf chlorophyll content index) for 11 genera (12 species) in a cool-temperate deciduous broadleaved forest in Japan. Knowing the leaf phenology of tree species is important for accurately evaluating the temporal variability of ecosystem functions (e.g., photosynthesis and evapotranspiration) under rapid climate change. However, there is a lack of freely available long-term observation data regarding leaf phenological characteristics for many tree species. We collected leaf phenological data from tagged shoots every 1-4 weeks from April or May to October or November each year from 2005 to 2014 in Takayama, Japan (36A degrees 08'46aEuro(3)N, 137A degrees 25'23aEuro(3)E, 1420 m a.s.l.). We targeted typical dominant, codominant, and understory tree species at the site. To evaluate differences among individuals and between sunlit and shaded leaves, we measured one to four shoots of some species and individuals. Our data provide input, calibration, and validation parameters for a terrestrial ecosystem and for radiative-transfer models and remote-sensing observations.