Figure 5.

Diurnal dynamics of NSC allocation in the overall architecture of the tree over 3 d. Pulse labeling of ¹³C was applied to a branch (branch ¹³C) for 2 h (dark vertical bars) in tree 1 (A, D, G, and J), tree 2 (B, E, H, and K), and tree 3 (C, F, I, and L). Levels of ¹³C were quantified in leaves (A–C), wood and bark of twigs (D–F), and wood at additional locations in the tree architecture, including trunk P and trunk C and in the roots (G–I). ¹³C atomic percent was compared with initial values to calculate APE. APE levels of the tissues from branch ¹³C (leaves, twig wood and bark, and branch wood; black symbols) were compared with natural variation in tissues from adjacent control branches (J–L; gray symbols in A–I). Gray ribbons around data points represent the sd for natural abundance (too small to show for the scale of A–I). ¹³C levels and variation observed in all of the branch tissues and in the trunk P exceeded natural variation. Shaded areas represent nighttime.