What’s that smell?
If you’re walking about and notice a fishy or rotten meat smell in the air, there could be an invasive Bradford pear tree near you.
Despite the foul odor, these trees, also known as Callery pear trees, are beautifully adorned with little clusters of white flowers.
“The blooms themselves are beautiful, but they stink,” said Billy Haag, forestry manager and certified arborist at Forest ReLeaf of Missouri. “They’re not attractive in any way when it comes to smell.”
Their relatively weak branches also make them a nuisance during storms, as limbs are easily scattered across the streets and yards where these plants are present. They became popular as street trees in the 1950s and ’60s, and today, the trees are widespread in and beyond Missouri across east and northern states.
Haag said the angle of Bradford pear tree branches make them weaker than other trees, so their life spans can be short. “When we talk about branching structure, we really like branches to be at a 90- to 45-degree angle,” Haag said. Bradford pear limbs grow vertically, resembling a pyramid or egg shape. And identifying them is easy when they are blooming, which usually occurs in early April as thick clusters of white flowers envelop the tree before leaves form.
Laura Chaves, the Horticulture Answer Service coordinator at the Missouri Botanical Garden, said the appeal of the pear tree is that it's inexpensive and grows easily — mature trees can become 30 to 40 feet tall. Chaves said each cultivar, or cultivated species of the Bradford pear tree, is self-sterile, meaning it doesn't produce viable seed.
“But if it crosses with a different cultivar, and there are about 26 cultivars of these trees out, then you get seed that is viable and the tree really grows very fast,” Chaves said. “It has this suckering habit, and what happens is the birds will eat the fruit, disperse the seeds and they pop up everywhere. They grow in pretty much any kind of soil, so they grow really easily and they just kind of colonize and sucker and take over naturalized areas and they can very easily crowd out our native plants.”
Fighting the intruders
HB 2412, introduced in January by state Rep. Bruce Sassmann, would effectively ban the sale of invasive plants like the Callery pear tree, including burning bush, climbing euonymus, Japanese honeysuckle and sericea lespedeza. Nurseries or nursery dealers that buy, sell or propagate the plants would have their certificate suspended by the Missouri Department of Agriculture.
The bill currently has no co-sponsors but is moving forward in the House. In honor of National Arbor Day, which is later this month, efforts to partner with community residents to replace the invasive trees are underway.
On Friday — Missouri Arbor Day — the Missouri Botanical Garden will be giving away noninvasive, native trees at the botanical garden’s Kemper Center for Home Gardening from 9 a.m. to 3 p.m. The event will continue on Saturday, and families will be allowed to receive one native tree per household that could include: buttonbush, redbud, persimmon, shortleaf pine, ninebark and chinkapin oak.
Chaves said the event typically is held annually but took a pause during the pandemic. The tree giveaway resumed last year, Chaves said. In addition to the Missouri Arbor Day event at the botanical garden, a “buyback” program will be hosted at nearly a dozen locations across the state on April 23. This event is the product of a partnership of the Missouri Botanical Garden, the Forest ReLeaf of Missouri, the Missouri Invasive Plant Council, the Forrest Keeling Nursery and the Missouri Department of Conservation.
“The profuse white blossoms of this highly invasive tree make their alarming spread especially apparent this time of year, along roadsides, in fields, parks and on private property,” said Carol Davit, chair of the Missouri Invasive Plant Council.
Residents who complete event registration and upload a photo of a cut-down Bradford/Callery pear tree by April 15 will receive a free native tree. On the registration form, participants will choose their event location and select the tree they’d like to receive.
Haag said the trees to be provided will come in three-gallon pots. Forest ReLeaf grows around 20,000 native trees each year.
“These trees, depending on the species, can range anywhere from two to five feet tall,” he said. “But they’ll have a full root system in that three-gallon pot. Most people are coming in a car like a sedan, and it’s easier to plant.”
