Fig. 1.

Mean biomass and assimilated portion of total ¹³C taken up by 18 detached sycamore branches allowed to transpire ¹³CO₂-labelled water for 4.75 h in sunlight. One-half of the branches were harvested at the end of the uptake period, and one-half were harvested after an additional 4.75 h in the dark. (Pooled data shown.) Leaf tissue includes whole leaf, and vein and lamina subsamples. Woody tissue includes whole branch woody tissue, and upper and lower cortex and xylem subsamples. Other tissue includes stipule and new growth. Bars are standard error of the mean.