Global seed supply is too poorly understood to even speculate on its contribution to the regeneration of forests that are increasingly lost to disturbance, climate change, and extensive human management. Through data synthesis and collaborations with more than 100 international researchers, the Clark lab has established the mastif project and assimilated seed production data for 12.1 millition tree-years in more than 700 species from all vegetated continents. We are interested in:

• Tree size and age effects: does tree fecundity decline as tree grows larger and older (Qiu et al., 2021a)?
• Map of life and traits: are there limits to reproductive potential whereby species sacrifice seed size in order to produce more seeds, a size-numbers tradeoff (Qiu et al., 2022)?
• Soil effects: will access to resources mediate the limits to reproduction (Qiu et al., 2022)?
• Masting syndrome: what are the causes and consequences of mast seeding at a global scale (Qiu et al., in review)?
• Canopy characteristics: how will tree fecundity respond to canopy nutrients, including N, P, K, Ca, and Mg (Qiu et al., in prep)?
• Forest regeneration: do forest communities reorganize throughout the tree life stages including adult trees, fecundity, and seedling recruitment (Qiu et al., 2021b)?
• Climate effects: how does individual fecundity change along the latitude gradient from dry tundra to wet tropics (Journe et al., 2022)?

There are current four published papers listed in the following, one manuscript in review and can be requested here. There are also three papers in progress, with results available here.