At UI, a sustainable plant ‘zoo’

The University of Idaho’s pair of arboreta this month received the Garden Stewardship Award from the American Horticultural Society.

The award recognizes the university for its sustainability efforts at the C. H. Shattuck Arboretum, a 14-acre naturalized arboretum started in 1909, and the nearby — and more heavily visited — Arboretum and Botanical Garden, a 64-acre cultivated arboretum founded in 1982.

Paul Warnick, the UI’s arboretum horticulturist and superintendent, said he saw the call for award nominations and thought the university’s arboreta checked most of the boxes.

“We’ve done quite a bit for sustainability that we should brag about more,” Warnick said.

Warnick is the only full-time staff member for the Arboretum and Botanical Garden but has one year-round part-time staffer and three student employees who work full time in the summer.

The Arboretum and Botanical Garden uses reclaimed water on the entire garden, Warnick said.

The university worked with the city of Moscow in the 1970s to use the reclaimed water processed by the Moscow Water Reclamation and Reuse Facility. Warnick said while they do use some herbicides to keep the weeds away, they don’t use insecticides except for wasp control.

“There’s no way the arboretum would exist anywhere without the reclaimed water,” Warnick said.

Warnick has worked at the arboretum since 2000 and took over as the superintendent in 2003 after Richard Naskali, the former director of the arboretum, retired. Naskali was on the board which started the arboretum in 1982 and took over as director in 1987.

Naskali, Warnick said, oversaw the change of the garden from former farmland into a collection of plants from each geographical area of the world. The garden in its current state is far from the master plan drawn up before the arboretum started, but Warnick said that’s part of its strength. The original plan was to break the garden into sections; Europe, Asia, Eastern North America, Western North America and then recreate ecosystems for each one.

But that’s not how the garden grew. While it is still divided into geographical sections, it is more of a collection of trees, shrubs and other plants. Every plant, bench, plaque and trash can in the arboretum was paid for with donations.

“Everything in it is a gift — no tax money, no student money, no public money. It’s all paid for by donations,” Warnick said.

The first trees planted are lining the golf course on the north end, Warnick recalled. It was Easter Sunday and roughly 75 trees were planted by Rotary volunteers. Those trees were watered by volunteers with buckets for years before underground water pipes were laid. The developed garden is 45 acres but the entirety of the designated area includes about 20 additional acres of farmland located near a large red barn on the south end of the arboretum.

The garden is far from being done growing, Warnick said. In 2023, a rock wall was added on the south side of the arboretum and new trees and a mix of Palouse Prairie plants were planted nearby. The goal is for people to watch the trees grow and see how each one differs and to provide shade.

“When I do tours for little kids, I often call it a zoo for plants,” Warnick said. “It’s a pretty good comparison, there’s tons of different kinds of zoos in the world.”

For more on the award, see ahsgardening.org/2024-great-american-gardeners-awards. For a map and information on how to tour the Arboretum and Botanical Garden, visit uidaho.edu/dfa/facilities/arboretum/tour-maps

Nelson can be reached at knelson@dnews.com.