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.
Photos provided by the Daviess-Martin CISMA, taken by Midwest Drone Services
Now this is where we get into a discussion about WHY they are bad. This discussion involves native plants and their roles in our ecosystems. Native plants, the ones that were here before our continent was settled by Europeans, are vital to the health of native insect populations, both pollinators and food sources for wildlife. When non-native invasive plants move in, they take over that habitat and displace the native plants, sometimes even eliminating them, destroying the food web in the process. Are all non-native plants bad? No. It’s not the presence of non-native plants that destroys food webs. It’s the absence of native plants, the ones that are being crowded out by invasive plants like pears, honeysuckle, autumn olive, multiflora rose, burning bush and garlic mustard, just to name a few. Only a small percentage of non-native plants become invasive, but those that do have the ability to completely transform natural areas.
Conservationists are now heading up the war against invasive plants. Cooperative Invasive Species Management Areas (CISMAs) have been formed all over the state. Volunteers meet to work in public spaces like parks to identify and remove them and the federal government also has programs through the NRCS (Natural Resources Conservation Service) to help landowners remove extensive infestations affecting cropland and forests. The Marshall County SWCD is looking into forming a new CISMA with our neighbors up in St. Joseph County. There is a callout on May 11th if you are interested in learning more about it. The link to register is on our home page.
Now, back to the announcement part of this blog article. This spring MCSWCD received a generous grant from the Arrow Head Resource Conservation and Development Area to fund a cost share program that we named the "Pretty Invasive Pears Bounty Program". We will help you pay to remove and replace an invasive pear in your yard with a good native tree. The link to the application is also on our website home page. It is our hope that after learning what a problem they are, you and your neighbors will want to remove them, even though they are pretty. They ARE pretty....pretty awful and pretty invasive!