The Story of a Retired Consulting Arborist Growing Markham’s Urban Forest

Meet Peter, Certified Arborist, Master Gardener and LEAF volunteer. This Urban Forest Champion is a life-long tree advocate who is committed to sharing his knowledge and experiences and inspiring passion for the urban forest within others


I had the chance to connect with Peter to learn how he carved his way into the tree community and now, in his retirement, continues to make great strides in improving the urban forest in his own neigbourhood. 

How did you first become interested in the urban forest?

My childhood exposure to nature and trees impacted me throughout life. My childhood home backed onto Mimico Creek. We had a diversity of trees growing along the river edge. I built tree forts with friends and played games among the trees. I experienced Hurricane Hazel in 1954 and recall how these same trees played a significant role in reducing soil erosion by slowing the force of the swollen, raging river which had swept several homes away. 

I graduated from the University of Toronto with an Bachelor of Science degree with Honours in Forestry. One professor, Eric Jorgensen, was the first to offer a course called ‘Urban Forestry’. His influence steered my professional career. 

How did you find out about LEAF and how have you been involved?

In retirement, I was looking for an opportunity to share my tree knowledge with others. I attended several arboriculture conferences, and someone referred to LEAF. After a web search, I found LEAF and signed on as a volunteer. A few months later, I attended the Tree Tenders Volunteer Training

As a LEAF volunteer, I participate in many tree planting events. Working with other volunteer planters, chatting as we plant, makes the work fly by. There’s a strong feeling of accomplishment when the event comes to an end. It’s an enjoyable experience with no pressure to plant a specific number of trees and no criticism of your work, just good guidance.

Please share an interesting story or memorable moment from your experience with LEAF

I very much enjoyed the Tree Tenders course I attended at Humber Arboretum. It was extremely well organised and a very open and friendly atmosphere. I was impressed by the enthusiasm of the group – we were like sponges soaking up the knowledge.

What does the urban forest mean to you and what message would you like to share with others to encourage them to become involved?

I’m a senior – the number of birthdays I’ve had is ‘unlisted’. Retirees and seniors are always looking for something purposeful to engage in on their own schedules, without the bureaucracy they left behind in their professional careers. We enjoy sharing our knowledge and experiences and connecting with younger people – it makes us feel younger. Getting involved with LEAF at an older age allows you to become a role model for others.

Volunteering to help restore parklands and ravines is truly rewarding. Within my Thornhill community, a group of volunteer residents and I are working to restore Grandview Park, a 2-acre woodland. Our volunteers have removed invasive trees, shrubs and ground cover over several years. This year, we are ready to introduce more native plants. Under the guidance and in partnership with LEAF and the City of Markham, our volunteer residents will plant 600 native trees and shrubs. And to further engage the community in the ecology in Grandview Park, we are offering six nature-themed walks, led by passionate expert volunteers.

I strongly believe that staying tuned in to the tree community allows for people with shared passions to do tangible work towards a common goal. Show your passion by joining the LEAF team!


Register for our upcoming Volunteer Orientations to learn how you can join in the effort to improve the urban forest! 


Sarah Halonen is the Stewardship Coordinator at LEAF. 

Our Tree Tenders program is supported by Ontario Power Generation.