Stems
Due to the positioning of cameras, it was not possible to measure stem
xylem vulnerability simultaneously with other tissues, so this was
quantified on four individuals of the same age and size. One section of
stem was selected per plant between the root collar and the first
reproductive structures. Using a sharp razor blade, a window of around
20 mm was carefully cut to remove the epidermis and cuticle, exposing
the xylem. Water potential was monitored with a stem psychrometer as
above and image capture protocols were the same as described for the
petiole and peduncle.