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Tree Marker Profile: Liz Cobb

Posted: August 29, 2019

Tree marking involves the careful selection of trees for harvest, based upon a forest management prescription. In order to mark trees on Crown land in Ontario, a certification is required. The individuals who hold this certification are known as ‘Tree Markers.’

In order to get a better sense of what tree marking entails, Forests Ontario interviewed a series of tree markers across the province.


Liz Cobb
GIS & Silvicultural Forester for Ottawa Valley Forest Inc.

Communications Manager MJ Kettleborough had the pleasure of chatting with certified tree marker Liz Cob about forest management and why she is so proud of the work she does.

When did you get certified as a tree marker?

When I started my career, I worked as a Tree Marker for the Ministry of Natural Resources and Forestry, there was no certification requirement at that time.  When the management of forests on Crown Land was taken over by Sustainable Forest Licence holders, certification became a requirement.  As a Forestry Technician working for Ottawa Valley Forest I took Tree Marking Level 1 and Level 2 courses.

Have you ever had strange encounters in the forest?

One time I saw a boat hanging in a tree. It was the weirdest thing I ever saw! I’ve also seen strange goings-on. One time I heard this screeching in the woods and I just had to go investigate it. The curiosity was killing me! It turned out to be two porcupines mating… scared the daylights out of me!

Also, one time I was working an area of concern on a wetland and there was a moose standing in the pond! He saw me… he had a big rack… and he was leaping up and crashing down in the water trying to get out. It turned out that he had a broken leg. I was able to call someone to help him out of his misery.

Seeing wildlife is a big part of tree marking, you see bears, wolves, raptors, even skunks!

What is your favourite forest or bush?

White pine shelterwood. White pine is very challenging to manage and I love it for that reason.   It’s a mid-tolerant species and likes the amount of sunlight to be just so.   I enjoy working hard to maintain its integrity.

Do you have a memorable tree marking story?

I first started tree marking over 30 years ago and being a girl was a still a pretty novel idea to the guys in my tree marking crew, they just didn’t know what to make of it.  I was pretty timid back then, and I didn’t know exactly what to do.  One of the older lads in the crew liked to wind me up by hiding behind trees and pretending to be a bear. It got me every time!

What kind of person is suited to be a tree marker? 

Someone who is confident and comfortable being outdoors on their own. One of the biggest struggles that people have is that they think they are comfortable being in the bush by themselves, but when it comes down to it they really aren’t. I think a tree marker should also be driven and self-motivated. There’s very little supervision in this job and you need to push yourself. It’s a physically hard job, so being fit is important and you have to love being outdoors in that environment.

What do you think when people are critical of cutting down trees?

You know, I have the clear-cut spot for the Teachers’ Tour, and I love to explain why we use each of the silvicultural systems that we do. We harvest certain groups of trees differently based on their light requirements and what they need to regenerate. We use the selection system to manage tolerant hardwoods and we use clear-cut to manage intolerant hardwoods. The average person isn’t aware of how complex forest management is in Ontario and.

People say things like don’t cut down trees. People in the forestry sector love trees more than anyone! I think it’s important to educate people about forestry.

What are your hopes for the future of forestry?

I want us to be able to promote the use of our natural resources. I think if we eliminate plastics and non-reusable things and use our sustainable natural resources, like wood, instead, then the value of wood would increase and the forest industry would be more financially stable. And we would be improving the environment.

I’m proud of what we do, and I’m proud of the work we do promoting our forests. I don’t want to hide it.

Follow Ottawa Valley Forest Inc:

Interested in tree marking? Certification through the Tree Marker Training Program is necessary to become a tree marker in Ontario. This tri-level program is delivered by Forests Ontario and CIF. For more information, please visit