1,000-plus trees to be planted for Morton Arboretum's centennial
A couple of shovels, a patch of dirt, preferably in a no-mow zone, and some tiny seedlings are what you might expect from an Arbor Day ceremony.
But the Morton Arboretum in Lisle has loftier expectations.
To mark the 150th anniversary of Arbor Day and its own centennial year in 2022, the arboretum will begin a tree-planting spree across seven counties this April.
"What better way for us to celebrate our huge milestone birthday of 100 years than a big community tree-planting," said Murphy Westwood, the arboretum's vice president of science and conservation.
The arboretum aims to plant more than 1,000 trees throughout Cook, DuPage, Kane, Kendall, Lake, McHenry and Will counties to improve an urban forest threatened by climate change and invasive species.
A ubiquitous invader, European buckthorn is the most common species by stem count in the same seven-county region, according to the arboretum's latest tree census. European buckthorn accounted for 36% of stems in the 2020 census count. The woody shrub creates dense thickets that block sunlight to a forest's floor, preventing the regeneration of oaks and other native species.
"Buckthorn can basically very quickly dominate forest here, and it just sort of smothers everything out underneath it, and so we don't have that natural succession," Westwood said. "We don't have those young trees growing up to replace the old trees."
The arboretum will be planting young trees around schools, neighborhoods, parks and other areas. Trees will include a diverse mix of 17 species, including a special centennial selection of a rare and little-known linden.
Back in 1938, scions, or part of a grafted plant, of Zamoyski's linden were brought to the Morton Arboretum from Kornik Gardens in Poland.
One of the resulting trees, a fine specimen, stands near the arboretum's research and administration building, displaying clusters of buttery white flowers in the spring and a leafy tower in the summer.
Outside of the arboretum, Zamoyski's linden covers only roughly 6.5% of the Chicago area's urban forest, said Kris Bachtell, vice president of collections and facilities.
But it's demonstrated relative resistance to the leaf-munching Japanese beetle and adaptability to the region's climate, Bachtell said.
The arboretum encourages species diversity to prevent the spread of pests and diseases that plague specific types of trees. Maples, oaks, elms, serviceberries and buckeyes are among the trees that will be planted for the arboretum's 100th anniversary.
"When something like Dutch elm disease or emerald ash borer comes through, it can wipe out the entire population of the trees on your street," Westwood said. "So we are very focused on ensuring that there is a diversity of species in our urban forests so that it's more resilient to any one pest or disease that might come through."
The arboretum also is planting the seeds of environmental stewardship. At planting events, arboretum experts will share their expertise to "empower people to become tree champions themselves," Westwood said.
It's a fitting tribute to arboretum founder Joy Morton.
In the last years of his life, the salt magnate set out to reshape the grounds of his country estate into a botanical haven. His vision became a reality when he formally established the arboretum on Dec. 14, 1922.
A decade later, he wrote a letter to a friend about welcoming "hundreds of automobile visitors" on pleasant spring days.
Morton was "passionate about trees, not only just the act of planting trees. He wanted people to learn about them," said Rita Hassert, collections manager at the arboretum's Sterling Morton Library.
Arboretum staff will help people learn how to care for the newly planted trees, how to water, prune and mulch.
Tree experts already have been doing site visits for months to identify the "right tree for the right place," Westwood said. Some will be chosen because they're more tolerant of drought or soil conditions.
The arboretum will be purchasing, delivering and planting just over 1,000 trees at an estimated cost of more than $200,000. It's been fundraising and putting out a call to municipal governments and community groups to join in the centennial tree-planting effort.
Not content to merely plant seedlings, the arboretum has contracted with nurseries to provide trees ranging in height from about 5 to 10 feet.
Trees will get in the ground over three seasons: spring and fall 2022 and spring 2023.