Patrick Robinson
Malia Caracoglia, Molly Harrigan and Dylan Mendenhall, measure a tree with a dense growth of Ivy on its trunk.

Forest Monitoring team helps shape the future of Seattle's urban forest

The Seattle Department of Parks and Recreation, EarthCorps, Green Seattle Partnership (GSP), forest stewards and community volunteers are piloting a citizen science effort that engages Seattle residents in analyzing and monitoring the urban forest.

One team was working in Camp Long, near the South Loop Trail on Saturday Sept. 18 to assess the forest ecosystem in a small area that will be used as the basis for understanding the relative health of the urban forest in that area. The areas assessed have been predetermined and targeted to be "cleaned up" meaning invasive species such as Himalayan Blackberry and Ivy will be removed.

Malia Caracoglia, Program Coordinator for the GSP Forest Monitoring Team said, "We're collecting baseline data so that after next year, restoration will have occurred (...) and this 1/10th of an acre will represent this whole area that's going to be restored. It will be like a snapshot."

One of the first citizen science projects in the US to focus on urban forests, the Green Seattle Partnership Forest Monitoring Team engages communities in surveying the condition of their urban parks, forests and forested wetlands.

Ivy, holly, blackberry and laurel may make Seattle’s Parks seem lush and green, but in fact they are a huge menace that is rapidly destroying the forests of the “Emerald City.”

"Ivy, as it crawls up a tree, weighs it down," Caracoglia said, " then you have a little windstorm and there goes that tree."

Joining Caracoglia on the volunteer team were Molly Harrigan and Dylan Mendenhall. Harrigan is from Ballard and Mendenhall is a West Seattle resident. For Harrigan it's a new experience. "I like to be outside and I thought it would be good to learn more about our native and invasive plant species. I also live in an apartment so I only have potted plants around me and I thought it would be a good way to get dirty in the city and learn more."

For Mendenhall doing this work is an extension of a commitment he made some time ago. He's Forest Steward for Schmitz Park. "My mother was the first Forest Steward and worked with Ken Shaw who is the lead volunteer for Friends of Schmitz Park. I started in high school leading volunteer parties with my mom."

Restoration is happening throughout Seattle Parks aimed at bringing back native forests. But is it working? The GSP Forest Monitoring Team gets residents directly involved in gauging the effectiveness of restoration efforts that involve thousands of volunteer hours and dozens of Friends of Parks groups.

To make the assessment the team uses some simple but effective tools. They measure the height of trees with a 'clinometer" that computes the height by measuring the angle over distance and they take the "diameter at breast height" or DBH generally at 4.5 feet. The data is then entered into a PDA device which collects it. It is later put in a database, a report is built and sent to the Forest Steward for the area and the Seattle Parks Department.

It might surprise you to learn that some trees have relatively short life spans. Alders for example might only live 80 years while conifers will have far longer lives. As some of these trees die, invasive species could come to dominate and the forest, as you've known it, disappears. This is central to why assessments are done, and restoration put in motion based on the data collected.

The information teams like this gather is used to determine budgets for restoration efforts, grant writing, and is otherwise utilized to maintain and monitor urban ecosystems in parks like Camp Long.

For more information on habitat health in Seattle’s forests, visit

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Thank you citizen scientist

Just want to thank Molly and Dylan (and Dylan's mom) for all the time and energy you are putting into making Seattle's forests healthy. We have a friend visiting from Germany, and although she checked off the typical tourist sites, it's the almost primeval-feeling forest parks that she keeps returning to again and again (Schmitz, Ravenna, Discovery) - they are just such an extraordinary place to find in the midst of a city. She's even thinking of skipping the Space Needle to go visit another "jurassic park".

Glad to hear it

Sounds like a very cool project. Thanks for helping to get the word out about the pressing challenges on our urban forest and the people and programs who are helping to solve them!

Death to Ivy and Blackberries!!

We need this all over western Washington! not just Seattle!! My city is overrun with Ivy!! Plus there aren't enough conifers! Too many leafy trees not enough pine!!

Excellent Partnership!

I'm glad to see these 3 groups working together and engaging the citizens of Seattle. I look forward to reading about more accomplishments from this team. Excellent work!

Great Project / Great Partnership

Thanks for sharing this report. It sounds like a wonderful example of organizations and people working together to learn and restore our urban environment!

What a great program. Excited

What a great program. Excited to see that this type of thing is happening in Seattle. It is much needed!

Terrific Program

We hear lots of talk about conservation, but conservation will only stop environmental damage.

What I love about this program is that it rehabilitates an urban forest. It not only stops environmental damage but repairs it making our urban forests better. It's like turning back the clock on environmental hazards.

What a Terrific Program! Kudos to Seattle Parks & Recreation, EarthCorps and the Green Seattle Partnership!

Our forest

I really like that the community is engaged in restoring their own backyard. What a great way to feel ownership for nature, make an impact, and be educated!