Biomass and nitrogen content of petiole and rachis predict leaflet trait variation in compound pinnate leaves of plants

•We conducted a detailed field investigation for leaflet area, mass, nitrogen, and specific leaflet area from 63 plant species in 364 study plots across 92 sites.•We found a potential model to assess leaflet trait variation in compound pinnate leaves of plants based on both petiole and rachis.•Climate and phylogeny are potential effects on the prediction of the biomass and nitrogen content of linear elements on leaflet trait variation.