I was out of the office and out of the state the whole last week of March. The Price family embarked on another road trip, with our main destinations being Washington, D.C., northern Virginia, and Gettysburg, Pennsylvania. I enjoy traveling just about any time of year, but spring might be my favorite season. Different trees and shrubs can be found coming out in flower, with noticeable differences in what you find at higher and lower elevations and depending on whether one is on a north or south facing slope.

As we drove east along the Pennsylvania Turnpike and along other thoroughfares near urban

areas, I couldn’t help but notice the proliferation of a certain species of small to medium-sized trees

sporting a heavy load of white blossoms. Drive along Interstate 70 from Englewood to Huber Heights this time of year and you’ll see what I mean: Callery pear trees, everywhere.

At this point, I’ll turn the story over to Joe Boggs of OSU Extension, Hamilton County. He writes:

Callery pears are native to Asia. The species is named for a French missionary, Joseph Callery, who first collected the tree in 1858. Unlike many family members, Callery pears showed good resistance to bacterial fireblight. The disease wreaked havoc on the common fruiting pear. The original Callery pears were brought to the U.S. to provide an infusion of genes into fruiting pears with the goal to enhance fireblight resistance. Although the crosses fared poorly relative to fruit pears, the USDA researchers made the serendipitous discovery that some crosses showed intriguing characteristics that could be of interest to the nursery and landscape industry. The cultivar Pyrus calleryana ‘Bradford’ grew out of this plant breeding project and was the first Callery pear to be introduced into U.S. landscapes.

Bradford was an immediate hit with its snowy white flowers, lustrous green leaves, glossy-red fall color, and because of genetic self-incompatibility, it didn’t produce fruit, meaning there was no mess. The icing on the cake was its tolerance of bacterial fireblight and the fact that it would grow almost anywhere.

However, many began to note that the “no fruit” feature of Callery pears appeared to be changing. More and more fruits were showing up on the trees. They were generally treated as oddities and we were mostly concerned with the increased mess beneath heavily fruiting trees. We didn’t recognize the fruits were a sinister portent of things to come.

‘Bradford’ Callery pear was still largely self-incompatible. However, scientists established that other cultivars originating from slightly different plants (e.g. better branch structure) and then cloned, were

crossing. Birds were then eating the small fruits and pooping out nascent pears far beyond the parent

trees. Thus, Callery pears began to populate road right-of-ways, abandoned fields, and many natural

areas including wetlands. Thus concludes Joe Boggs’ excellent description of the situation.

In January, 2018, Callery pear was listed as an invasive species by the Ohio Department of Agriculture. Fast forward to five years later in January, 2023, when Callery pear became illegal to sell in the State of Ohio. Other states even have buyback programs that provide replacements trees to landowners who cut down Callery pear trees. What seemed to be the perfect landscape plant turned out to be a menace. It just goes to show that hindsight is always 20/20.

Reach BJ Price at 937-456-5159 for more information.