It is amazing how inefficient water use seems to be in plants.

Dry biomass growth is ~1kg/m^2/year, wet maybe 4-5x that. But they see ~1m of rainfall, so 1000kg/m^2/year of water. The roots fail to take up some, but the rest seems to be ~99% lost due to transpiration (some of which is necessary for heat stress and/or pump up nutrients).

Maybe after C4 rice we can get C4/CAM coffee?