Want to contribute to a citizen science program looking at how trees interact with pollutants in different types of environments?


Students from across Canada are invited to be part of the Trans-Canadian Research and Environmental Education (TREE) Project. TREE is a citizen science program done in partnership between the CLS and the Mistik Askîwin Dendrochronology Laboratory (MAD Lab). Students can help researchers study how trembling aspen trees thrive in different environments across Canada. Sampling kits are lent out and we cover the costs of shipping.

High School, Middle Years, or Adult Basic Ed.

Flexible Timeframes

Land-Based, Distance Learning

Data from the dendrochronology lab and the synchrotron is collected from these samples and is added to our citizen science database, where anyone can access, compare, and investigate further! This program is well-suited for classes in environmental sciences, chemistry, biology, land-based education, math, and more. Check out our Teaching Resources section for more info. Participation is open year-round and can easily fit into a lesson, unit, or classroom field-trip.

NSERC (logo in image) supports Student Programs and shipping of kits with the CLS Education Team.The Canadian Light Source is proud to offer the TREE Program and we acknowledge the support of the Natural Sciences and Engineering Research Council of Canada (NSERC) PromoScience to make this possible.


All the information shared below, including the registration form, data, and downloadable resources, can be found on our TREE website.

TREE Website

How It Works

Listed below is a general outline of activities for participating in TREE. With participation open year-round, you can start these activities at any time. Note though that there are certain times in the calendar year when data cannot be collected at the synchrotron; samples can still be collected and sent in! The Education Team is available to clarify and assist with any aspect of the program, just get in touch.

You can also check out the TREE Overview Document which provides more detail about the program, what is covered in the modules, an example of the connections to curricular outcomes, and how to ship samples.

Students from La Ronge, SK / Treaty 6 and the Traditional Homeland of the Métis, using the borer to get TREE samples.
  •  Learning material and data is available for teacher or student access as needed for your schedule
  • Teacher completes the registration form to access a sample collection kit
  • CLS Education Team member contacts teacher and a TREE kit is booked
  • Class is sent a kit with tools for sample collection
  • Students research events in the sampling area and create a detailed timeline of all events that might impact tree growth (i.e. natural/environmental, industry, human, and climate events)
  • Students collect samples from trembling aspen and nearby soil from sampling area 
  • Samples, sample form, and the timeline (electronic version preferred but printed version acceptable) are sent to the CLS and the MAD Lab for data analysis
  • Data is shared with students and teacher once processing is complete - this time frame is unpredictable - a report is provided as it becomes available
Data from samples is then shared with the citizen science database where students can analyze and compare their results with other classes across Canada!


Project Partners

The TREE Program is a full partnership between CLS Education and the Mistik Askîwin Dendrochronology Laboratory (MAD Lab; logo in image).The CLS is excited to be working in partnership with the Mistik Askîwin Dendrochronology Laboratory (MAD Lab) in delivering the TREE program. The MAD Lab was launched in the spring of 2014 after moving to Saskatoon from Mount Allison University. The MAD Lab was formed to investigate tree ring related research questions in many areas of Canada and now through the tree ring chronologies they have created, the MAD Lab is able to understand the climate history of various location, date historical artifacts, and investigate how environmental contamination from humans has changed over time. Visit MAD Lab's website to learn more.

The MAD Lab is lead by Dr. Colin Laroque (shown in the next image, top left), a professor in Soil Science and School of Enviroment and Sustainability at the University of Saskatchewan. Colin is registered Métis and shares his knowledge of trees through his ongoing research and conversations with trees. Check out his interview with the Climate Atlas of Canada where he speaks more on his unique perspective as a Métis scholar. 

With the TREE program, MAD Lab is investigating the adaptability of trembling aspen (Populus termuloides) to toxins in environments across Canada. Trembling aspen are quite abundant throughout Canada, although not all of Canada, and they tolerate, even thrive, with much higher levels of toxins in their soil than other species of trees. They can potentially be used to remediate contaminated sites. In order to study this, a large and varied sample size of this species is required and this is where students from across Canada can help!

Teaching Resources

Students crowding around Dr. Colin Laroque at MAD Lab, learning about how tree cores are mounted to holders to collect dendrochronology data.

To help support collection of the samples and student understanding, various resources have been made. Check out our TREE modules both in print and electronic form, providing content to help expand on the citizen science aspect of the program as well as downloadable lesson plans you can incorporate into your classroom. There are also videos that provide instruction and background knowledge to the program. We continue to develop our resources and look to incorporate more Indigenous Ways of Knowing and meaningful content.

What kind of content can you expect to find in TREE? Students will be learning about the life and nutrient cycles of trees, connecting to their communities, applying that knowledge to decipher their data from the tree rings, and learning how soil plays a role. TREE takes on an interdisciplinary approach and is adaptable to connect with curriculum across many subjects in Grades 6-12. We have provided an example of curricular connections with Grade 8 curricula across Canada. Check out our resources to see if TREE can fit in your class!


Participation in this program requires that you commit to helping your students:

  • Construct a timeline on the various impacts in the environment in the area you are sampling,
  • Collecting and sending to us at least 2 trembling aspen tree cores with associated soil samples according to instruction, and
  • Sending the kit, samples, a sample form, and timeline back to us. 

Kits are booked for approximately 1 week at a time for sampling. Registration is open all year but there may be certain times that are better for collecting (winter does pose some challenges). Also, be aware that synchrotron data can only be collected when there is beam available and this will impact processing of samples. We process samples sent to us as quickly as we are able to, but cannot guarantee a specific timeframe. Contact us if you have questions and/or keep an eye on the TREE calendar or operations schedule (looking for green, normal day shifts) for when data can be collected.