Studies of photosynthesis and diffusion resistance in paper birch (Betula papyrifera Marsh.) with synthesis through computer simulation.

Canopy structure and physiology of paper birch are examined in the field during two growing seasons. Leaves are found to be steeply inclined in the upper canopy levels and foliage mass is located higher in the canopy than frequently observed in more shade tolerant species. Functional relationships between the controlling environmental factors and the physiological processes of leaf resistance to water vapor diffusion and gross photosynthesis are used in a computer simulation model to examine production and water use aspects of paper birch.