ABSTRACT
In the move from the water to land, plants evolved traits that allowed them to cope with their new environment. Arguably, the most dramatic problem they faced was the relative dryness of air. Rapid water loss from photosynthetic tissues requires equally rapid water supply. Poor water transport capabilities limited the earliest nonvascular plants to small size [1]. The evolution of xylem vastly increased hydraulic conductance and contributed to the diversification of plant size evident today [2,3].
