(The following is a guest post by Penn State Brandywine undergraduate student researcher Ami Iannello)
Three students at Penn State Brandywine were given the opportunity to do a six-week engaged scholarship project at Tyler Arboretum. Students Erin Hawk, Ami Iannello, and Ben Coon have been visiting Tyler Arboretum weekly to collect data for their research project. Erin and Ami have been collecting measurements such as the height and circumference of the historic trees in the Painter Collection, while Ben has been taking photos of the same trees and collecting the GPS coordinates in order to work with generating a custom Google Map for the project. Erin and Ami have entered their measurement into a site called “PhillyTreeMap.” This site is a crowd-sourced database which utilizes the tree height and circumference from a measured tree and computes the “ecobenefits” and how many dollars per year a specific tree (example: energy conserved, stormwater filtered, etc.), is saving our community, just by simply being there.
It may be a little confusing as to what “measuring” the trees really means. To collect their data, Erin and Ami have been using numerous tools and techniques in order to communicate the most accurate information to their audience.
To measure the tree circumference, the girls identified where they would measure around the tree trunk at four feet six inches off of the ground. They then used a tape measure, being sure the tape measure stayed level around the trunk, to measure each tree circumference. For bumpy trees, Erin and Ami measured the narrowest point anywhere below the four feet six inches. For leaning trees, they measure the four feet six inches in a diagonal with the lean. Finally, with multi-trunk trees, the girls measured each trunk separately, being sure not to add the circumferences together.
To measure tree height, Erin and Ami had to take a different approach, because, of course, they could not simply use a tape measure for this portion of their project. The girls used a method described by Utah State University Extension with a yardstick in which they measured the distance from their eye to the tips of their fingers along a yardstick on themselves and made a line. Next, one of the girls walked backwards, however many feet, holding the yardstick straight with her line at the bottom of the tree until the yardstick was the height of the tree. With a rolling distance measuring wheel, the other girl started walking from the base of the tree to the heel of her partner in order to calculate the height. Erin and Ami preformed this task three times from multiple angles around the tree and took the average of the three numbers in order to record the most accurate height of each tree.
Here is an example of one of the historic trees at Tyler Arboretum that was measured along the Scenic Loop and the “Yearly Ecosystem Services” in which it provides:
Yearly Ecosystem Services for the Tulip Tree (Liriodendron tulipifera), as calculated by PhillyTreeMap
A part of the Historic Tree Collection at Tyler Arboretum
|Carbon dioxide stored to date||7,683.9 lbs||$25|
|Energy conserved||2,262.3 kwh/year||$285|
|Carbon dioxide removed||674.2 lbs/year||$2|
|Air quality improved||6.0 lbs/year||$28|
|Stormwater filtered||6,213.3 gal/year||$61|
This information highlights that historic trees at Tyler Arboretum, such as this tulip tree, are not only beautiful to admire and historic in value, but all of Tyler’s trees have a positive impact on the environment and society around them.
We will be continuing to work on collecting our data, and we will share our results, along with Ben’s Google Map, at the end of the summer – stay tuned!