treeage 1

Have you often looked at the large trees on your property and wondered how old they are?

We know that trees can be aged by counting the growth rings within the trunk, but this is a difficult task without cutting the tree down. Coring is also problematic.

However, the WA Department of Environment and Conservation, Science Division has produced a summary paper counting the growth rings of about 200 trees and correlating the number of rings with the circumference of the tree. It is valid for both Jarrah and Marri. In particular the summary paper references  Whitford (2002), as well as other research.

With this data, we can measure the circumference of the tree and estimate its age.

Jarrah Marri Tree Age Plot


Here is the summary paper with eth details... pdfJarrah_and_Marri_tree_age.pdf


Roleybushcare has simplified the process even more.

We have marked-up two fibreglass tape measures so they read in 'tree years'. All you need to do is borrow one of the tapes from Roleystone Hardware (thanks to Sue for her help) then loop the tape around the tree at 1.3 m height and read the age from the tape measure.

Members of Roleybushcare measured the largest tree they found in Stinton Cascade Nature Reserve during a recent field day – it was 285 years old.

Do you have an older one on your block? We are keen to find the oldest tree in Roleystone/Karragullen so please borrow a tape, measure your biggest Jarrah and Marri tree and then either give Roleystone Hardware your results or send the data to This email address is being protected from spambots. You need JavaScript enabled to view it..

Click here to learn how to identify your Marri or Jarrah tree.