Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.

Subtropical and tropical wetlands play a prominent role in the global carbon (C) cycle; yet factors that influence their C fluxes remain uncertain. We collected measurements from a temporarily flooded subtropical wetland over 3 years to investigate environmental drivers impacting CO₂ and CH₄ fluxes. The wetland was a sink of CO₂ (−469 to −380 g C‐CO₂ · m⁻² · year⁻¹) and a source of CH₄ (25.1 to 32.1 g C‐CH₄ · m⁻² · year⁻¹) to the atmosphere. Dry season CH₄ emissions represented 41 to 49% of the annual budget, reflecting the importance of continuous CH₄ flux measurements. Gross primary productivity (GPP) increased with temperature and radiation, and the influence of VPD on GPP varied with soil inundation. Higher water tables decreased R_eco and increased GPP, and a higher GPP in turn lead to enhanced R_eco likely through enhancements of GPP on autotrophic respiration. This suggests that the impact of the water table on R_eco depends on the cancelling effects of hydrology and GPP. Emissions of CH₄ increased with soil temperature, water table, and GPP until soils were inundated at which point temperature and GPP became the main drivers. Water table and temperature influenced GPP and CH₄ fluxes, and increases in GPP directly enhanced CH₄ emissions. In addition to impacting C fluxes directly through water table depth, hydrology also determined the hierarchy of the dominance of factors controlling C fluxes and their response. The positive climate forcing of subtropical wetlands may be dictated by plant‐mediated and climate interactions, with hydrological factors playing a major role in determining the greenhouse gas sink or source strength of subtropical wetlands.