UMaine undergraduate students play a key role in developing forestry technology
by Jesse Bifulco, Maine EPSCoR media intern
It can be challenging for researchers and tree farmers to get their hands on the precise equipment they need to monitor their ecosystems. A dendrometer, an automated measurement device that wraps around a tree’s trunk, can provide insights into growth and health. These measurements are critical to monitoring ecological resources, but dendrometers can be expensive to install and maintain. To help address this, researchers and students at the University of Maine’s Center for Research in Sustainable Forests (CRSF) are developing their own cost-effective option for automated wireless tree measurement.
The project seeks to create a new kind of band dendrometer with funding from the NSF EPSCoR RII Track-2 project, “Leveraging Intelligent Informatics and Smart Data for Improved Understanding of Northern Forest Ecosystem Resilience” (INSPIRES; OIA-1920908) and E-RISE RII project, “Enhancing Maine Forest Economy, Sustainability, and Technology Ecosystem To Accelerate Innovation” (FOREST; OIA-2416915) grants. Leo Edmiston-Cyr, dendrometer project lead and technical computer programmer for CSRF, is working with two volunteer undergraduate engineering students, John Hodson (senior, electrical engineering) and Josiah Bloom (senior, mechanical engineering), whose contributions have been substantial.
CSRF’s dendrometer, called the INdendro, will be able to provide real-time tree growth data transmitted remotely with little manual labor. The INdendro is sensitive enough to measure tiny changes of about a micrometer in a tree’s perimeter. These measurements have many direct applications, such as assessing growth and forecasting future changes. Constant automated data transcription also allows for dating weather events and growth periods. The INdendro seeks to make this information easy to access for landowners via a companion application that receives real-time data.
The project began out of necessity. No other dendrometers offered the combination of features that CSFR needs for their work. “The combination of a band dendrometer with a low-power, long-range wireless network is unique to INdendro.” Edmiston-Cyr explained. “There aren’t any truly comparable dendrometer systems.” Most market dendrometers are point dendrometers, an alternative technology drilled into a tree and only measures growth in one spot. This limitation in resolution makes point dendrometers less reliable than band dendrometers. Additionally, no other dendrometers offer wireless data transmission at an affordable price. The INdendro promises to be competitively priced at approximately $100 a unit once final production begins. For comparison, that is roughly the price of the cheapest available point dendrometer, which does not offer wireless capability.
When Hodson and Bloom joined the project, the prototype INdendros still had to be assembled by hand in a time-consuming process. Hodson’s job was to design a computer board and schematic that could be factory printed to speed up production, but he had to pivot before final production when the chosen computer chip became unavailable due to the COVID-19 chip shortage. To Hodson, this challenge was a test of flexibility and patience. “I had to take several steps back and redesign major portions of INdendro. In the process of these redesigns, I found several mistakes in my original design that I was able to fix accordingly. By working through these unexpected challenges, I developed a much better device.”
Bloom, working on the body and tension mechanism of the device, reflected saying he hopes to see the final product mass-produced for research throughout New England and beyond. His design prioritizes simple assembly while remaining durable enough to spend years in the elements. The current working designs, deployed in Pinkham Notch, New Hampshire and Nutting Preserve, Maine, have already been operating for the past two years. “For this project, I became the person my teammates relied on for mechanical design decisions,” remarked Bloom. “I learned to trust my expertise while making critical engineering choices.”
The INdendro pushes past the capabilities of market dendrometers by utilizing LoRa radio transceivers which can afford long range with low power requirements and operate in the 915MHz ISM band. The maximum range is about 600 meters – depending on conditions – and allows for many dendrometers over a wide area to connect to a single base station. Edmiston-Cyr summarized the project’s importance not just to researchers, but also to resource managers. “The entry cost is extremely low. The installation is extremely simple. It grants the ability to instrument your asset and know how it’s performing for you.”
The project is reaching its final stages of development. Once the test batch is finished, Edmiston-Cyr and his team can produce the units at scale. The CSRF, through the Cooperative Forestry Unit, cooperates with many landowners who will be among the first offered to use the tool. Thanks to its innovation, affordability and ease of use, the INdendro will be a powerful tool for tree monitoring.