Our Callery Pear Buy-back events, both scheduled for April in St. Louis and Columbia, have been postponed indefinitely. However, we still encourage property owners to cut the trees during spring (when they are easy to identify) as a means to reducing populations from spreading.

Thank you for doing your part to help slow the spread of this invasive species!

As you remove Callery pear and other invasive plants, please send us a photo to [email protected] or mention us on Twitter and Facebook @moinvasives.

Here’s a quick overview on:

  • how to control Callery pears on your property
  • what to do if you currently don’t have the means to remove these invasive trees, and
  • how to spread awareness about invasive plants beyond your backyard.

Callery Pear invading roadside near Highway 50. Photo by Bill Ruppert.

What’s the problem with Callery pears?

Callery pear (Pyrus calleryana) is a popular ornamental tree native to China. Several cultivars of the tree are offered commercially, including ‘Aristocrat’, ‘Autumn Blaze’, ‘Bradford’ (which is the commonly planted “Bradford pear”), ‘Capital’, ‘Cleveland,’ ‘Chanticleer’, ‘Redspire’, and ‘Whitehouse’.

When cultivars in the “Callery pear” family cross-pollinate, their fertile seeds sprout up and aggressively take over areas where they aren’t wanted. Escaped Callery pear can grow densely along roadsides, unmowed fields/meadows, open woods, or any other open areas. Emerging seedlings will require up to 3 years to be noticeable from a distance, and up to 5 years before trees begin to flower. 

We define an invasive plant species as “an aggressive, non-native species whose presence causes or is likely to cause economic harm, environmental harm, or harm to human health.” These species grow and reproduce rapidly. 

MoIP is most concerned with invasive species because of their direct negative impacts. Callery pear, for instance, is costly to remove and devastating to the habitats where they crowd out native vegetation that is nutritious for local wildlife.

We are encouraging property owners to identify the trees during spring (when they are easy to identify) and remove them from your property as a means to prevent populations from spreading.

OK, I see I can help by removing Callery pears from my own property. What’s the best way to do that?

Use flagging tape to mark your Callery pear trees while in bloom when they are easiest to identify. You can return to the tree and treat it when you are ready. Photo by Felicia Amman.

The following advice comes from Dr. Reid Smeda, University of Missouri Extension, for the Missouri Invasive Plant Task Force:

Control of trees is easier when they are small.

Do not mow seedlings or small trees, as single stem trees will re-emerge as multiple stem trees.

To control trees from seedlings to about 6 feet tall, leaves can be treated with some formulation of glyphosate. An effective rate is 2-4 quarts per acre of a concentrated form (not the Ready-To-Use formulation) of glyphosate. If you want to mix only one total gallon of spray solution, add 4-8 ounces of concentrated glyphosate to 1 gallon of water. Mix the herbicide in water and add a small amount of surfactant (0.5% of final volume). Spray the solution on pear leaves and be sure to cover the entire tree. Be careful to avoid spraying adjacent desirable vegetation, because glyphosate can damage that also. Trees can be treated once leaves come out in the spring until leaves turn color in the fall. Damage symptoms are slow to develop (30 days) and complete control of treated plants can take up to 7 months.

An alternative to treating Callery pear leaves is to treat the base of the tree. Optimum timing for this technique is fall through early winter. Pour a small amount of a concentrated form of glyphosate into a small open-mouth jar. Identify a small, 1 inch diameter, disposable paint brush. Add a small amount of food coloring to the jar and stir to dissolve the food coloring (I like red or blue). No surfactant is needed. Using a chain saw or other saw, cut the Callery pear tree down and make the final cut across the base of the trunk until only a short (about 1 inch) stump is visible. Within 20 minutes of the final cut, paint the top of the stump with a thick coating of the red-colored glyphosate. If control is effective, you will not see any shoots come from the base of the stump.

Be sure to wear gloves and all proper protective equipment as described on the glyphosate label.

Let’s help our native trees and get rid of Callery pear!

I don’t have a chainsaw or other control methods available right now. Is there anything I can do now to stop the invasion of Callery pear trees?

Yes! We encourage you to identify the trees in April while they are flowering and mark the tree with flagging tape or another secure, visible marker. You can go back and control the tree whenever you are ready.

Use flagging tape to mark your Callery pear trees while in bloom when they are easiest to identify. You can return to the tree and treat it when you are ready. Photo by Felicia Amman.

Please make sure you are identifying Callery pear properly. Callery pear limbs generally grow vertically, forming a pyramid or egg shape. In early April, very dense clusters of white flowers cover the tree before leaves form. In maturity, they reach heights of 30 to 40 feet.

See below for more information on proper identification:

Where can I get help having my Callery pear professionally removed?

Please refer to the Grow Native! Resource Guide listings for Arborists and Land Care & Landscape Services to find professionals in your area who can assist with tree removal. These companies are on board with the Grow Native! mission to protect and restore biodiversity.

The Missouri Invasive Plant Task Force is housed under the Missouri Prairie Foundation’s Grow Native! program.

How can I spread more awareness about Callery pear?

We all have a role to play in educating the public about invasive species and their impact on the economy and environment in Missouri and other places we love.

  • Plant native Missouri plants on your property. Learn more at GrowNative.org
  • On social media, share your photos of cutting down your own Callery pear with the facts provided above. Please tag us @moinvasives on Twitter and Facebook, and use the hashtag #InvasivePlant so we can share in your successes!
  • Engage your neighbors, local business owners, and other connections in conversation about invasive plants.
  • Ask your political representatives at the state, local and national level to support invasive species control efforts.

Remember, email us at [email protected] with a photo of your Callery pear removal. We will stay in touch with information about future Buy-backs.

Thank you again for doing your part.