The right way to measure and model plant carbon balance

Plant carbon balance determines growth, carbon storage and perhaps resistance to stress. Most terrestrial carbon cycle models and measurements of plant carbon balance assume that photosynthesis drives growth. This assumption is wrong because the environmental controls of growth are more sensitive than those of photosynthesis. Consequences: models will not make correct predictions, and incomplete measurements  of carbon balance may yield the wrong inference about cause and effect. Models should include sink control, and measurements should be made of all carbon balance components.