Long-term flowering records of herbaceous plants in Tokyo, Japan during 1994-2015 through citizen science

We provide a 22-year period (1994–2015) dataset of flowering records of herbaceous plant species in Tokyo, Japan. Trained volunteers of the citizen group conducted field surveys using a citizen science approach. During monthly surveys, the volunteers recorded the flowering phenology of plants in an area of the Institute for Sustainable Agro-ecosystem Services and Tanashi Forest (The University of Tokyo) in Nishitokyo City, Tokyo, Japan. In all, 5982 observations on 401 species including 11 subspecies, 44 varieties, 6 forma from 70 families of herbaceous plants were collected in Tokyo. These data provide an overview of the flowering phenology of herbaceous plants in urban areas, where regular monitoring is often difficult due to the environment being highly urbanized and subject to intensive weed control. The complete data set for this abstract published in the Data Paper section of the journal is available in electronic format in MetaCat in JaLTER at http://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP-2021-05.1/jalter-en.