22 CityTREES
When I first explored wood with an environmental
scanning electron microscope (ESEM), the beau-
tiful structures that came into view took my
breath away. Unlike electron-scanning microscopy
(ESM) with a standard microscope, with ESEM the
wood does not need to be dried out to be scanned
successfully, and it gives you a 3D look into green-
wood. This is far superior to making wood slides
with a microtome [instrument that cuts extremely
thin sections of material for examination] and
then looking under a standard microscope, as that
process only gives you a 2D view. The images in
this pictorial are courtesy of ESEM technology.
These are among the images generated when I did my PhD at the
University of Manchester, England. Because I was working on this equip-
ment for the first time, my images are amateur in quality, and most of
them relate to fractured surfaces. Better images of wood structures
are available from ESM experts, but for teaching I find it advanta-
geous to use my own images, about which I know the full context.
Unlike my previous articles in City Trees, this one has a struc-
ture much like a set of presentation slides, building up a picture
of some interesting components of the wood of angiosperms and gym-
nosperms. When I put these slides up in a classroom, I often
say to the students, "Welcome to Planet Wood!" I enjoy taking
them on a bit of a journey, and I hope you enjoy this one.
—Duncan Slater
Adventures in Wood
with Dr. Duncan Slater