Spring is in the air in St. Louis, but so is a stinky odor — if you recently caught a whiff of something nasty, it might have been a Bradford pear tree.
“The flowers are not pleasant,” said Billy Haag, forestry manager and certified arborist at Forest ReLeaf of Missouri. “They're good for the eyes but not so much for the nose. They stink.”
These trees aren’t just pungent, they’re also invasive in Missouri. As they begin to flower, local organizations are relaunching their annual effort to encourage people to get rid of them.
Callery pears are invasive trees that include the Bradford cultivar. Until mid-April, if Missourians remove a Callery pear from their property, they can get a free native tree through a buyback program run by the Missouri Invasive Plant Council, Forest ReLeaf of Missouri, Forrest Keeling Nursery and the Missouri Department of Conservation.
The non-native, invasive pear trees are harmful to the local environment because they can grow out of control, said Jean Ponzi, green resources manager with EarthWays Center of the Missouri Botanical Garden.
“When you drive along any of our highways here at the end of March, the first days of spring, all those white flowering trees you see along the highways and going up the sides of forested roadways, those are all Callery pear,” Ponzi said. “Those are all an invasive species that have escaped cultivation.”
The trees originally became popular in the U.S. with landscapers looking for trees to decorate suburban streets.
“People just went bananas for it,” Ponzi said. “It's a small tree. It's a beautiful, compact shape. It has lovely spring flowers, lovely autumn color.”
At the time, people thought the trees were sterile, but that turned out to be wrong. As humans planted more varieties, they cross-pollinated with each other and started to reproduce and escape captivity.
“They grow so vigorously, and they can grow anywhere, that they're pushing out our native plants, which are displacing some of our wildlife species as well,” Haag said.
The pear trees have other qualities that make them problematic. They grow in a V shape that isn’t as strong as native trees, Haag said.
“When we have ice storms, wind storms, a lot of heavy wind like we've been having recently, they're very vulnerable to breakage, so it's a hazard to humans walking by, as well as our cars and property,” Haag said.
On top of the buyback program, there is also a bill in the Missouri legislature that would prohibit the sale of Callery pears and some other non-native invasive species, including Japanese honeysuckle.* It passed the Senate, but the House has not taken action in the past month.
For people who can prove they’ve recently taken down a Callery pear, Forest ReLeaf is offering multiple trees that are native to Missouri, including oaks, shortleaf pines, hackberries and pecans. Haag said the eastern redbud and the black gum are going fast so far.
“Our native trees have evolved with our native insects and wildlife for thousands of years, so by planting our native trees, you're directly providing food source, habitat, pollen for all of those things that are buzzing, flying and scurrying around your yards,” Haag said.
Last year, the buyback’s free trees were claimed within 48 hours, Haag said.
“That's not the case this year, so there’s still plenty of time to register,” Haag said. “We have a decent amount of trees and diverse species left too.”
*Correction: "A Missouri bill would prohibit the sale of Japanese honeysuckle."
