On a sunny Arbor Day, 20 Polson Middle School students traipsed to O’Malley Park to plant a trio of purple robe locust trees, under the supervision of Polson Parks and Recreation employees.

The students were part of an eighth-grade leadership class taught by Nicole Camel and Tessa Hupka.

“It’s kind of having fun in the sun – we’re planting trees, making shade, and being part of something,” said student Adin Hunt.

“What’s cool in my opinion is this is going to be around for a while and future generations can see it,” said her classmate, Edgar Vejez Pete. “I can come back when I’m older and hopefully see these trees because I’m sure they’ll be taken care of. It’ll be a nice little tourist attraction, a nice stroll to come out here, and you can enjoy a baseball game in the shade.”

The trees, with some littleleaf lindens still to come, take the place of three giant cottonwoods that were cut down from the southwest corner of the park last fall. The flowering locusts, which grow up to 50 feet tall and are adorned with long purple tendrils in the spring, are planted on a slope above the baseball field.

“If you’re taking trees out it’s always good to put some back in,” said John Campbell of Delaney’s Landscape Center.

Patrick Nowlen, head of the parks department, said the trees were funded by an $850 grant from the Arbor Day Foundation; Delaney’s and Mission Lawn and Landscape also donated materials for the project.

According to Nowlen, the city plants trees annually on Arbor Day. Last year six were added at the Polson Skate Park. This year, “we scaled back to three, but we got bigger trees,” he said.

Before they started planting, Campbell asked eighth graders what trees give to the community. Shade, prettiness, oxygen and homes for birds were some of the answers he received.

He added to the list: “They help filter the water before it gets to the lake and they help filter air as well. Aesthetics is a good one – green is the most soothing color – and they’ll provide shade for everybody watching baseball, plus this is a nice open area for people to hang out in during the summer.”

He also said purple robe locusts are part of the legume family, meaning they fertilize themselves.

“You know what symbiosis is?” he asked. “These trees have little microbes that live in the roots and bacteria that take nitrogen out of the air and give it to the plant, which in turn gives them a little sugar to survive.”

Eighth grader Zephyr Sternick discovered a trick for measuring the correct circumference of the holes they were digging by measuring the container with the shovel and then laying the shovel across the hole to make sure it was big enough.

Other lessons? “I learned that trees work together, and that Bridger is good at digging holes.”