Examination of embolisms in maple and birch saplings utilising microCT

March 7, 2023

Our team have recently published a journal paper describing the application of synchrotron x-ray micro tomography (microCT) to non-invasively examine the internal structure of a maple and a birch sapling.  

J. Robinson, M. Rennie, M. Clearwater, D.J. Holland, A.K van den Berg, M. Watson. 2023. Examination of embolisms in maple and birch saplings utilising microCT. Micron, 168. 103438.  

To examine mechanisms of sap exudation, we have been using non-invasive imaging techniques to investigate sap behaviour within the maple xylem, the region through which sap is transported. In particular, we have focused on vessel embolisms. Vessels are like pipes that transport sap from the root to the crown, and embolisms are pockets of gas that form within these vessels. 

Our research mapped out the embolisms within the sapling in three dimensions to evaluate the size distribution, showing that most of the saplings’ total embolised volume is made up of large embolisms over 0.005 mm3 in volume. We also observed that birch has a more uniform distribution of embolisms than maple.

Example of a micro-computed tomographic image of a sugar maple branch section showing (left) a three-dimensional reconstruction, with a small section cut out to show the inner regions (right) a transverse two-dimensional slice of the branch section. The zoomed in region shows both sap-filled(arrowheads) and embolized vessels (white arrows). [credit: Tenaya Driller]