Plant Invaders – Callery Pears

After an early start, then a bad freeze, this spring has settled into normalcy. In Delaware that means some glorious warm sunny days and some cold, windy, rainy days.  We’ve had an opportunity to enjoy lots of spring flowers that have been long-lasting as the weather stayed cool. One set of flowers I was not excited to see though, were the blooming Callery pears. These early flowering trees have started to clog our roadsides. They are overtaking woodland edges and many unmanaged landscapes. While you may find blooming white trees on the roadside attractive, the sad truth is they are crowding out native trees like serviceberry, dogwood and sassafras that should be blooming along in wood edges and roadsides in the spring.  How did this happen?  Bradford pears, the dominant Callery pear planted ubiquitously in the 80’s and 90’s did not produce fruit, so it didn’t spread into open landscapes.  But, it was replaced with a wide variety of cultivars bred for better branch angles to reduce the problem of splitting limbs, that plagued Bradford pears.  The wide variety of cultivars resulting in cross pollination so now Callery pears are prolific fruit and seed producers.  And that means they are everywhere!

If it bothers you that an invasive exotic species is now the dominant tree on Delaware’s roadsides, there is something you can do—remove the pears at your home and from any landscape you control.  That won’t help with those that have already escaped into unmanaged landscapes, but if everyone removed Callery pears from their property (as well as the other popular landscape plants on the Delaware Invasive Species list – burning bush, Norway maple, Japanese barberry, and privet, to name a few) we could start to make a difference in protecting our natural areas and preserving our native trees, shrubs and perennials.  It is true that what one person does won’t matter, but if everyone removes invasive plants on their property the collective effort will matter.

The good news is when you remove plants, you get to replace them with new species.  You can select native trees and shrubs that will enhance your landscape enjoyment and attract native wildlife to your garden.  For suggestions on what to buy, try consulting a Delaware Certified Nursery Professional (CNP).  The Delaware Nursery and Landscape Association, in conjunction with Delaware Cooperative Extension developed a program to certify professionals in the nursery and landscape industry.  This is a voluntary certification, but it is a good way to ensure you are hiring or buying from a professional.  Delaware CNPs purchase and study a manual and then pass a difficult exam that tests their knowledge of plants, soils, diseases, insects, weeds and many other aspects of landscape management.  If you want to find out whether a business employs CNP’s, consult the DNLA website (

Certified Nursery Professional LogoLook for this logo to identify Certified Nursery Professionals in the nursery and landscape industry.