Sheridan Trims Down Its Invasive Tree Population

Apr 26, 2019

Gov. Mark Gordon has stated he wants Wyoming to be a leader in fighting against invasive species. The city of Sheridan is taking that seriously by ridding the community a troublesome tree.

This spring, the community is removing 10 acres of Russian olive trees. The tree was heavily planted in the early 20th century as a windbreak and because it could easily survive in Wyoming's climate.

The Russian olive is a big tree with silvery-white leaves that don't fall off in the winter. In the spring and summer, the trees have yellow or white flowers and bright red berries. Often they're found near bodies of water like ponds or rivers.

Sheridan city arborist Clark Van Hoosier said the problem is that it's crowding out native species.

"It's able to spread through a lot of seeds, it's able to spread through its root systems. So usually if you have one Russian olive, you're going to have a group of Russian olives. What we're finding is that they're getting thick enough to where they are out-crowding our native species," Van Hoosier said.

Communities in the state declared war on the Russian olive tree in 2007, when it was classified as a noxious weed, meaning it can't be sold as nursery stock. By law, each county has to come up with a control plan.

The Sheridan Community Land Trust (SCLT) received a Natural Resource Trust grant to work on the project. Land trust executive director Brad Bauer said he's excited to get the project off the ground.

"This particular project with the city of Sheridan is really exciting because we are working with a certified arborist who knows way more about trees and tree management than I would ever be able to put into my head," Bauer said.

Arborist Van Hoosier and the SCLT have created a plan to remove and maintain the trees.

"Our process basically is just hand felling the trees with chainsaws and dragging them out by ourselves a lot of the times. We also got a Bobcat out here to drag some of the bigger pieces," Van Hoosier said.

"Then we've rented a chipper to put all the material through because it makes us a lot easier to haul out, and we get nice wood chips we can take up and use in the future."

Rather than just dumping the Russian olive trees, they are trying to take a more useful approach.

Chris Vrba with the Sheridan Community Land Trust said when they plant the native trees, the Russian olive will be part of that process.

"Those saplings that will be planted will actually be jump-started with the mulch from the Russian olive," Vrba said. "So the invasive plant that was in there displacing these native species is actually going to be used to get it a jump-start in the future, which is kind of like the circle of life, right?"

The new trees will be species such as cottonwoods, chokecherries, and Ponderosa pines. In all, seven native species will be planted in place of the Russian olive, Van Hoosier said.

"Rather than an acre of one species of Russian olives, we'd rather have an acre of four or five different species that have different benefits for different parks," he said.

Van Hoosier notes not all the Russian olives will be gone from town.

"Some people got the idea that we're going to come through and clear cut in our parks. And that's not what we're doing. We're managing. We're leaving some on the landscape," he said. "We're trying to take a lot of them off because there is a lot but we're leaving some too. Because you know it is hard to grow trees in Wyoming so you know we want to keep some of the ones we have around."

Van Hoosier's hope for the project is that when they are done, Sheridan's parks can become an example for thriving native species through the increase of diversity.

For now, the saplings will symbolize the growth to come.

Officials said they hope to expand the project beyond Sheridan's borders. SCLT's Bauer said this particular project includes partial funding for landowners in and around Sheridan who want to remove Russian olives from their property.

"We developed this project out of the interest to not only help remove this invasive species where we can, but also to develop and explore relationships with new partners, not only the city of Sheridan but also private landowners," Bauer said.

Bauer's hoping this project will allow for more collaborative projects with landowners on other serious issues.