Ornamental Pears - Pretty, and Pretty Invasive

Updated: Oct 12, 2021

This blog article is meant to be both informative and serve as an announcement. It is also overdue, it should have been written several weeks ago when the ornamental pears were in full bloom so that it would have been easier to point out the evidence of their invasion, it was obvious then. If you were reading or watching any news at all, though, you probably saw something about them. It was all over Facebook! There were numerous posts about them by The Nature Conservancy, the Indiana Department of Natural Resources, and various Soil and Water Conservation Districts. But just a few days ago, a friend asked me WHY they are so bad. I’ve decided that I need to take some time to explain why ornamental pears have become the archenemy to anyone that wants to keep our ecological community healthy. I will start out with a brief history of them, one that very few people know about.

In the early 1900’s, researchers discovered that a Callery pear from Asia was highly resistant to a disease called fireblight that was devastating to the fruit pear industry in California. It was believed that by using this pear for rootstock it would add disease-resistance to the pears. A botanist was sent to China in search of a super pear. Seeds were selected and sent back to be tested. During the research, it was discovered that these pears had the potential to be a tough ornamental street tree. A thornless selection with very small fruit was chosen and tested in a suburb in Washington D.C. They proved to be able to grow in any soil and have that profile that embodied America’s idea of perfect mass-produced uniformity. The selection was named ‘Bradford’ after someone involved in its development and was released into the nursery industry in the early 1960’s. They took off in popularity. Everyone loved them….growers, homeowners and developers. But they had an Achilles heel. They were susceptible to wind damage. Major wind damage, with trees splitting completely in half during a storm. Breeders went back to work and developed additional cultivars. Some names that you may recognize include ‘Aristocrat’, ‘Cleveland Select’, ‘Capital’ and ‘Redspire’. The original pears were sterile, but when any two cultivars were together, they produced a heavy fruit set that was dispersed by the birds. And just like that, the stage was set for the invasion