Meet the WTS Board - Gervais Sawyer, and wood boring weevils

The Wood Technology Society
18 Oct 2019

Gervais Sawyer

As befits his name, Gervais Sawyer has had an affinity with saws from an early age. As farmer's boys, he and his brother were put to work, as soon as they were able, cutting trees and logs for the fire. When it came to choosing a career, the timber trade was a more attractive prospect than 6am milking.

After 12 years of very varied experience in every aspect of the timber industries and many nights of night school studying for the IWSc exams, he left the industry to start teaching about all things wood. Gervais reflects on the joy of having worked with so many inspirational people.

He is currently editor of International Wood Products Journal which is a task that gives him the delight of daily education and the opportunity to meet inspirational people at conferences. For many years he has been exhibiting at careers fairs, wood fairs and schools, trying to interest young people in our huge (but almost invisible) industry.

He has an alter-ego, The Saw Doctor, offering short YouTube videos on wood technology.

When there is a break, he enjoys musical instrument and furniture making.

“My wood science passions?  It is difficult to choose one because wood has so many amazing properties.  For example, its tensile strength never ceases to amaze me.

But to list something unusual, my family were amused when I got passionate about a particular wood boring weevil. My work includes inspecting wooden marine structures, which usually fail by decay fungi or marine borers such as gribble (Limnoria) or shipworm (Teredo).  On one inspection I chanced upon numerous weevils that were shaped like little hand-bells. Both the larvae and the adults were feeding on the partly decayed wood. What immediately caught my interest was that these were immersed at high tide. The respiration and osmotic challenge to these beetles is immense.


Back in the laboratory, I found that if you drop them into water they go into suspended animation. Take them out of water a week later, and after about 10 minutes they walk away, none the worse!

Under the scanning electron microscope you can see that dirt is kept out of the head/body socket by beautiful fan-like brushes.  Its name is Pselactus spadix (Latin for chestnut coloured hand-bell shaped).  They are easy to keep as pets!  They don't skitter around, just slowly plod along.

The full biology of Pselactus spadix was studied by Dr. Pascal Oevering.  Although only 2.5 to 3mm long, Geoff Cooper (a researcher at BRE) had the incredibly sensitive touch to dissect the animal revealing its crop and gut structure.”

Pselactus spadix adult head capsule brushes

Pselactus larva diverticuli